Subjects
 English Language Arts
 Math
 Science
 Social Studies
Skills
N/APros: Helps students develop confidence and clearly track progress; teachers get immediate stats on their students' trouble spots.
Cons: Drilling limits opportunities for kids to apply skills in realworld ways and questions include toofrequent repetition.
Bottom Line: Students can improve targeted skills with tons of practice modules and visually appealing tasks.
IXL provides class and individual reports with item analysis, usage, and trouble spots that allow parents and teachers to get the specific information they need to differentiate instruction for their kids. The standard Trouble Spot report is very useful for quickly identifying where students are having a hard time and which students need extra help, and the Recommendations page gets students working on questions at their level right away, across the breadth of topics that IXL provides. To set an appropriate math level for each student, have them regularly complete the Diagnostic tool, which narrows down where they should currently focus.
PreK kids may have a hard time with navigation at first and might benefit from some verbal directions. Fortunately, the site offers audio support for grades PreK through 2. Older students may also need some guidance as to which skills they should practice, though. Teachers can suggest skills for classes to practice, but there's no way for teachers to assign certain tasks to specific students or groups of students through the dashboard.
IXL can be a useful resource for teachers all over the world, as there are editions for many countries that are tailored to fit local curricula and standards. The Inspiration section includes professional learning services to help teachers get the most out of IXL, along with printable resources, and textbook and Common Core alignments.
Continue reading Show lessIXL is a website and Chrome app with thousands of math, language, social studies, science, and Spanish practice questions and modules that meet nearly all the Common Core State Standards (CCSS) for K12 and some of the Next Generation Science Standards (NGSS) for grades 25. You'll find games covering the fundamentals through subjectspecific high school lessons.
Math lessons cover PreK to 12th grade and include questions such as comparing fractions using real recipes, classifying a system of equations, and graphing two equations by dragging points. Language arts practice  again, PreK to 12th grade  focuses on grammar and vocabulary skills. Science and social studies each cover 2nd through 8th grade topics. Spanish learners can complete Level 1 of the language.
Students practice one skill at a time and earn points and ribbons when they get questions correct. Once they reach 100 points for a skill, kids earn a stamp in their book, encouraging them to master other skills to earn virtual prizes. Practice sessions are timed. Questions within a section are often very repetitive, but students looking for variety can jump around from topic to topic under the Recommendations section.
The targeted activities in IXL  pretty much drillandpractice in format and approach  can provide extensive opportunities for independent practice. Unlike many sites where students do drills, though, IXL gives feedback on how to get better. Incorrect answers are explained thoroughly with written explanations and examples. These explanations may help strong readers, but a multimedia approach would support a wider range of learners.
Overall, IXL's focus on repetition and its lack of variety in question format are its major drawbacks. However, it gives students the tools they need to improve in many subjects and build confidence across the board, allowing for independent targeted practice with immediate feedback. And, the site's personalized skill recommendations help keep things fresh. Still, IXL's learning isn't wellintegrated across each subject.
Overall Rating
Engagement Is the product stimulating, entertaining, and engrossing? Will kids want to return?
When it comes to drill and practice, you can only make it so much fun. However, IXL makes a good effort through rewards, immediate feedback, and visually appealing tasks.
Pedagogy Is learning content seamlessly bakedin, and do kids build conceptual understanding? Is the product adaptable and empowering? Will skills transfer?
Practice, practice, practice builds confidence and accuracy, though repetition won't encourage critical thinking. Students do occasionally have some say in what to work on next, however.
Support Does the product take into account learners of varying abilities, skill levels, and learning styles? Does it address both struggling and advanced students?
Students get detailed support and tips when they get a problem wrong. The preK through secondgrade content has microphone icons that read a problem out loud. Curriculum is aligned to CCSS, the NGSS, and other state standards.
Key Standards Supported
Arithmetic With Polynomials And Rational Expressions
 HSA.APR.1
Understand that polynomials form a system analogous to the integers, namely, they are closed under the operations of addition, subtraction, and multiplication; add, subtract, and multiply polynomials.
 HSA.APR.6
Rewrite simple rational expressions in different forms; write a(x)/b(x) in the form q(x) + r(x)/b(x), where a(x), b(x), q(x), and r(x) are polynomials with the degree of r(x) less than the degree of b(x), using inspection, long division, or, for the more complicated examples, a computer algebra system.
 HSA.APR.7
(+) Understand that rational expressions form a system analogous to the rational numbers, closed under addition, subtraction, multiplication, and division by a nonzero rational expression; add, subtract, multiply, and divide rational expressions.
 HSA.APR.3
Identify zeros of polynomials when suitable factorizations are available, and use the zeros to construct a rough graph of the function defined by the polynomial.
 HSA.APR.4
Prove polynomial identities and use them to describe numerical relationships. For example, the polynomial identity (x2 + y2)2 = (x2 – y2)2 + (2xy)2 can be used to generate Pythagorean triples.
 HSA.APR.5
(+) Know and apply the Binomial Theorem for the expansion of (x + y)n in powers of x and y for a positive integer n, where x and y are any numbers, with coefficients determined for example by Pascal’s Triangle.1
Building Functions
 HSF.BF.1
Write a function that describes a relationship between two quantities.
 HSF.BF.2
Write arithmetic and geometric sequences both recursively and with an explicit formula, use them to model situations, and translate between the two forms.
Circles
 HSG.C.5
Derive using similarity the fact that the length of the arc intercepted by an angle is proportional to the radius, and define the radian measure of the angle as the constant of proportionality; derive the formula for the area of a sector.
 HSG.C.1
Prove that all circles are similar.
 HSG.C.2
Identify and describe relationships among inscribed angles, radii, and chords. Include the relationship between central, inscribed, and circumscribed angles; inscribed angles on a diameter are right angles; the radius of a circle is perpendicular to the tangent where the radius intersects the circle.
 HSG.C.3
Construct the inscribed and circumscribed circles of a triangle, and prove properties of angles for a quadrilateral inscribed in a circle.
 HSG.C.4
(+) Construct a tangent line from a point outside a given circle to the circle.
Conditional Probability And The Rules Of Probability
 HSS.CP.1
Describe events as subsets of a sample space (the set of outcomes) using characteristics (or categories) of the outcomes, or as unions, intersections, or complements of other events (“or,” “and,” “not”).
 HSS.CP.2
Understand that two events A and B are independent if the probability of A and B occurring together is the product of their probabilities, and use this characterization to determine if they are independent.
 HSS.CP.6
Find the conditional probability of A given B as the fraction of B’s outcomes that also belong to A, and interpret the answer in terms of the model.
 HSS.CP.9
(+) Use permutations and combinations to compute probabilities of compound events and solve problems.
Congruence
 HSG.CO.1
Know precise definitions of angle, circle, perpendicular line, parallel line, and line segment, based on the undefined notions of point, line, distance along a line, and distance around a circular arc.
 HSG.CO.2
Represent transformations in the plane using, e.g., transparencies and geometry software; describe transformations as functions that take points in the plane as inputs and give other points as outputs. Compare transformations that preserve distance and angle to those that do not (e.g., translation versus horizontal stretch).
 HSG.CO.3
Given a rectangle, parallelogram, trapezoid, or regular polygon, describe the rotations and reflections that carry it onto itself.
 HSG.CO.4
Develop definitions of rotations, reflections, and translations in terms of angles, circles, perpendicular lines, parallel lines, and line segments.
 HSG.CO.5
Given a geometric figure and a rotation, reflection, or translation, draw the transformed figure using, e.g., graph paper, tracing paper, or geometry software. Specify a sequence of transformations that will carry a given figure onto another.
 HSG.CO.6
Use geometric descriptions of rigid motions to transform figures and to predict the effect of a given rigid motion on a given figure; given two figures, use the definition of congruence in terms of rigid motions to decide if they are congruent.
Counting And Cardinality
 K.CC.6
Identify whether the number of objects in one group is greater than, less than, or equal to the number of objects in another group, e.g., by using matching and counting strategies.1
 K.CC.7
Compare two numbers between 1 and 10 presented as written numerals.
 K.CC.4
Understand the relationship between numbers and quantities; connect counting to cardinality.
 K.CC.5
Count to answer “how many?” questions about as many as 20 things arranged in a line, a rectangular array, or a circle, or as many as 10 things in a scattered configuration; given a number from 1–20, count out that many objects.
 K.CC.1
Count to 100 by ones and by tens.
 K.CC.2
Count forward beginning from a given number within the known sequence (instead of having to begin at 1).
 K.CC.3
Write numbers from 0 to 20. Represent a number of objects with a written numeral 020 (with 0 representing a count of no objects).
Creating Equations
 HSA.CED.1
Create equations and inequalities in one variable and use them to solve problems. Include equations arising from linear and quadratic functions, and simple rational and exponential functions.
 HSA.CED.2
Create equations in two or more variables to represent relationships between quantities; graph equations on coordinate axes with labels and scales.
 HSA.CED.3
Represent constraints by equations or inequalities, and by systems of equations and/or inequalities, and interpret solutions as viable or non viable options in a modeling context. For example, represent inequalities describing nutritional and cost constraints on combinations of different foods.
 HSA.CED.4
Rearrange formulas to highlight a quantity of interest, using the same reasoning as in solving equations. For example, rearrange Ohm’s law V = IR to highlight resistance R.
Expressing Geometric Properties With Equations
 HSG.GPE.5
Prove the slope criteria for parallel and perpendicular lines and use them to solve geometric problems (e.g., find the equation of a line parallel or perpendicular to a given line that passes through a given point).
 HSG.GPE.6
Find the point on a directed line segment between two given points that partitions the segment in a given ratio.
 HSG.GPE.7
Use coordinates to compute perimeters of polygons and areas of triangles and rectangles, e.g., using the distance formula.
Expressions And Equations
 6.EE.1
Write and evaluate numerical expressions involving wholenumber exponents.
 6.EE.2
Write, read, and evaluate expressions in which letters stand for numbers.
 6.EE.3
Apply the properties of operations to generate equivalent expressions.
 6.EE.4
Identify when two expressions are equivalent (i.e., when the two expressions name the same number regardless of which value is substituted into them). For example, the expressions y + y + y and 3y are equivalent because they name the same number regardless of which number y stands for.
 6.EE.5
Understand solving an equation or inequality as a process of answering a question: which values from a specified set, if any, make the equation or inequality true? Use substitution to determine whether a given number in a specified set makes an equation or inequality true.
 6.EE.6
Use variables to represent numbers and write expressions when solving a realworld or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.
 6.EE.7
Solve realworld and mathematical problems by writing and solving equations of the form x + p = q and px = q for cases in which p, q and x are all nonnegative rational numbers.
 6.EE.8
Write an inequality of the form x > c or x < c to represent a constraint or condition in a realworld or mathematical problem. Recognize that inequalities of the form x > c or x < c have infinitely many solutions; represent solutions of such inequalities on number line diagrams.
 6.EE.9
Use variables to represent two quantities in a realworld problem that change in relationship to one another; write an equation to express one quantity, thought of as the dependent variable, in terms of the other quantity, thought of as the independent variable. Analyze the relationship between the dependent and independent variables using graphs and tables, and relate these to the equation. For example, in a problem involving motion at constant speed, list and graph ordered pairs of distances and times, and write the equation d = 65t to represent the relationship between distance and time.
 7.EE.3
Solve multistep reallife and mathematical problems posed with positive and negative rational numbers in any form (whole numbers, fractions, and decimals), using tools strategically. Apply properties of operations to calculate with numbers in any form; convert between forms as appropriate; and assess the reasonableness of answers using mental computation and estimation strategies. For example: If a woman making $25 an hour gets a 10% raise, she will make an additional 1/10 of her salary an hour, or $2.50, for a new salary of $27.50. If you want to place a towel bar 9 3/4 inches long in the center of a door that is 27 1/2 inches wide, you will need to place the bar about 9 inches from each edge; this estimate can be used as a check on the exact computation.
 7.EE.4
Use variables to represent quantities in a realworld or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.
 7.EE.1
Apply properties of operations as strategies to add, subtract, factor, and expand linear expressions with rational coefficients.
 8.EE.7
Solve linear equations in one variable.
 8.EE.8
Analyze and solve pairs of simultaneous linear equations.
 8.EE.5
Graph proportional relationships, interpreting the unit rate as the slope of the graph. Compare two different proportional relationships represented in different ways. For example, compare a distancetime graph to a distancetime equation to determine which of two moving objects has greater speed.
 8.EE.6
Use similar triangles to explain why the slope m is the same between any two distinct points on a nonvertical line in the coordinate plane; derive the equation y = mx for a line through the origin and the equation y = mx + b for a line intercepting the vertical axis at b.
 8.EE.1
Know and apply the properties of integer exponents to generate equivalent numerical expressions. For example, 32 × 3–5 = 3–3 = 1/33 = 1/27.
 8.EE.2
Use square root and cube root symbols to represent solutions to equations of the form x2 = p and x3 = p, where p is a positive rational number. Evaluate square roots of small perfect squares and cube roots of small perfect cubes. Know that √2 is irrational.
 8.EE.3
Use numbers expressed in the form of a single digit times an integer power of 10 to estimate very large or very small quantities, and to express how many times as much one is than the other. For example, estimate the population of the United States as 3 × 108 and the population of the world as 7 × 109, and determine that the world population is more than 20 times larger.
 8.EE.4
Perform operations with numbers expressed in scientific notation, including problems where both decimal and scientific notation are used. Use scientific notation and choose units of appropriate size for measurements of very large or very small quantities (e.g., use millimeters per year for seafloor spreading). Interpret scientific notation that has been generated by technology.
Functions
 8.F.1
Understand that a function is a rule that assigns to each input exactly one output. The graph of a function is the set of ordered pairs consisting of an input and the corresponding output.1
 8.F.2
Compare properties of two functions each represented in a different way (algebraically, graphically, numerically in tables, or by verbal descriptions). For example, given a linear function represented by a table of values and a linear function represented by an algebraic expression, determine which function has the greater rate of change.
 8.F.3
Interpret the equation y = mx + b as defining a linear function, whose graph is a straight line; give examples of functions that are not linear. For example, the function A = s2 giving the area of a square as a function of its side length is not linear because its graph contains the points (1,1), (2,4) and (3,9), which are not on a straight line.
 8.F.4
Construct a function to model a linear relationship between two quantities. Determine the rate of change and initial value of the function from a description of a relationship or from two (x, y) values, including reading these from a table or from a graph. Interpret the rate of change and initial value of a linear function in terms of the situation it models, and in terms of its graph or a table of values.
 8.F.5
Describe qualitatively the functional relationship between two quantities by analyzing a graph (e.g., where the function is increasing or decreasing, linear or nonlinear). Sketch a graph that exhibits the qualitative features of a function that has been described verbally.
Geometric Measurement And Dimension
 HSG.GMD.3
Use volume formulas for cylinders, pyramids, cones, and spheres to solve problems.
 HSG.GMD.4
Identify the shapes of twodimensional crosssections of three dimensional objects, and identify threedimensional objects generated by rotations of twodimensional objects.
Geometry
 1.G.1
Distinguish between defining attributes (e.g., triangles are closed and threesided) versus nondefining attributes (e.g., color, orientation, overall size); build and draw shapes to possess defining attributes.
 1.G.3
Partition circles and rectangles into two and four equal shares, describe the shares using the words halves, fourths, and quarters, and use the phrases half of, fourth of, and quarter of. Describe the whole as two of, or four of the shares. Understand for these examples that decomposing into more equal shares creates smaller shares.
 2.G.1
Recognize and draw shapes having specified attributes, such as a given number of angles or a given number of equal faces.5 Identify triangles, quadrilaterals, pentagons, hexagons, and cubes.
 2.G.3
Partition circles and rectangles into two, three, or four equal shares, describe the shares using the words halves, thirds, half of, a third of, etc., and describe the whole as two halves, three thirds, four fourths. Recognize that equal shares of identical wholes need not have the same shape.
 3.G.1
Understand that shapes in different categories (e.g., rhombuses, rectangles, and others) may share attributes (e.g., having four sides), and that the shared attributes can define a larger category (e.g., quadrilaterals). Recognize rhombuses, rectangles, and squares as examples of quadrilaterals, and draw examples of quadrilaterals that do not belong to any of these subcategories.
 3.G.2
Partition shapes into parts with equal areas. Express the area of each part as a unit fraction of the whole. For example, partition a shape into 4 parts with equal area, and describe the area of each part as 1/4 of the area of the shape.
 4.G.1
Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in twodimensional figures.
 4.G.2
Classify twodimensional figures based on the presence or absence of parallel or perpendicular lines, or the presence or absence of angles of a specified size. Recognize right triangles as a category, and identify right triangles.
 4.G.3
Recognize a line of symmetry for a twodimensional figure as a line across the figure such that the figure can be folded along the line into matching parts. Identify linesymmetric figures and draw lines of symmetry.
 5.G.3
Understand that attributes belonging to a category of two dimensional figures also belong to all subcategories of that category. For example, all rectangles have four right angles and squares are rectangles, so all squares have four right angles.
 5.G.4
Classify twodimensional figures in a hierarchy based on properties.
 5.G.1
Use a pair of perpendicular number lines, called axes, to define a coordinate system, with the intersection of the lines (the origin) arranged to coincide with the 0 on each line and a given point in the plane located by using an ordered pair of numbers, called its coordinates. Understand that the first number indicates how far to travel from the origin in the direction of one axis, and the second number indicates how far to travel in the direction of the second axis, with the convention that the names of the two axes and the coordinates correspond (e.g., xaxis and xcoordinate, yaxis and ycoordinate).
 5.G.2
Represent real world and mathematical problems by graphing points in the first quadrant of the coordinate plane, and interpret coordinate values of points in the context of the situation.
 6.G.1
Find the area of right triangles, other triangles, special quadrilaterals, and polygons by composing into rectangles or decomposing into triangles and other shapes; apply these techniques in the context of solving realworld and mathematical problems.
 6.G.2
Find the volume of a right rectangular prism with fractional edge lengths by packing it with unit cubes of the appropriate unit fraction edge lengths, and show that the volume is the same as would be found by multiplying the edge lengths of the prism. Apply the formulas V = l w h and V = b h to find volumes of right rectangular prisms with fractional edge lengths in the context of solving realworld and mathematical problems.
 6.G.3
Draw polygons in the coordinate plane given coordinates for the vertices; use coordinates to find the length of a side joining points with the same first coordinate or the same second coordinate. Apply these techniques in the context of solving realworld and mathematical problems.
 6.G.4
Represent threedimensional figures using nets made up of rectangles and triangles, and use the nets to find the surface area of these figures. Apply these techniques in the context of solving realworld and mathematical problems.
 7.G.1
Solve problems involving scale drawings of geometric figures, including computing actual lengths and areas from a scale drawing and reproducing a scale drawing at a different scale.
 7.G.3
Describe the twodimensional figures that result from slicing three dimensional figures, as in plane sections of right rectangular prisms and right rectangular pyramids.
 7.G.4
Know the formulas for the area and circumference of a circle and use them to solve problems; give an informal derivation of the relationship between the circumference and area of a circle.
 7.G.5
Use facts about supplementary, complementary, vertical, and adjacent angles in a multistep problem to write and solve simple equations for an unknown angle in a figure.
 7.G.6
Solve realworld and mathematical problems involving area, volume and surface area of two and threedimensional objects composed of triangles, quadrilaterals, polygons, cubes, and right prisms.
 8.G.9
Know the formulas for the volumes of cones, cylinders, and spheres and use them to solve realworld and mathematical problems.
 8.G.6
Explain a proof of the Pythagorean Theorem and its converse.
 8.G.7
Apply the Pythagorean Theorem to determine unknown side lengths in right triangles in realworld and mathematical problems in two and three dimensions.
 8.G.8
Apply the Pythagorean Theorem to find the distance between two points in a coordinate system.
 8.G.1
Verify experimentally the properties of rotations, reflections, and translations:
 8.G.2
Understand that a twodimensional figure is congruent to another if the second can be obtained from the first by a sequence of rotations, reflections, and translations; given two congruent figures, describe a sequence that exhibits the congruence between them.
 8.G.3
Describe the effect of dilations, translations, rotations, and reflections on twodimensional figures using coordinates.
 8.G.4
Understand that a twodimensional figure is similar to another if the second can be obtained from the first by a sequence of rotations, reflections, translations, and dilations; given two similar two dimensional figures, describe a sequence that exhibits the similarity between them.
 8.G.5
Use informal arguments to establish facts about the angle sum and exterior angle of triangles, about the angles created when parallel lines are cut by a transversal, and the angleangle criterion for similarity of triangles. For example, arrange three copies of the same triangle so that the sum of the three angles appears to form a line, and give an argument in terms of transversals why this is so.
 K.G.4
Analyze and compare two and threedimensional shapes, in different sizes and orientations, using informal language to describe their similarities, differences, parts (e.g., number of sides and vertices/“corners”) and other attributes (e.g., having sides of equal length).
 K.G.1
Describe objects in the environment using names of shapes, and describe the relative positions of these objects using terms such as above, below, beside, in front of, behind, and next to.
 K.G.2
Correctly name shapes regardless of their orientations or overall size.
 K.G.3
Identify shapes as twodimensional (lying in a plane, “flat”) or three dimensional (“solid”).
Interpreting Categorical And Quantitative Data
 HSS.ID.1
Represent data with plots on the real number line (dot plots, histograms, and box plots).
 HSS.ID.2
Use statistics appropriate to the shape of the data distribution to compare center (median, mean) and spread (interquartile range, standard deviation) of two or more different data sets.
 HSS.ID.3
Interpret differences in shape, center, and spread in the context of the data sets, accounting for possible effects of extreme data points (outliers).
 HSS.ID.6
Represent data on two quantitative variables on a scatter plot, and describe how the variables are related.
Interpreting Functions
 HSF.IF.7
Graph functions expressed symbolically and show key features of the graph, by hand in simple cases and using technology for more complicated cases.
 HSF.IF.8
Write a function defined by an expression in different but equivalent forms to reveal and explain different properties of the function.
 HSF.IF.9
Compare properties of two functions each represented in a different way (algebraically, graphically, numerically in tables, or by verbal descriptions). For example, given a graph of one quadratic function and an algebraic expression for another, say which has the larger maximum.
 HSF.IF.4
For a function that models a relationship between two quantities, interpret key features of graphs and tables in terms of the quantities, and sketch graphs showing key features given a verbal description of the relationship. Key features include: intercepts; intervals where the function is increasing, decreasing, positive, or negative; relative maximums and minimums; symmetries; end behavior; and periodicity.
 HSF.IF.5
Relate the domain of a function to its graph and, where applicable, to the quantitative relationship it describes. For example, if the function h(n) gives the number of personhours it takes to assemble n engines in a factory, then the positive integers would be an appropriate domain for the function.
 HSF.IF.6
Calculate and interpret the average rate of change of a function (presented symbolically or as a table) over a specified interval. Estimate the rate of change from a graph.
 HSF.IF.1
Understand that a function from one set (called the domain) to another set (called the range) assigns to each element of the domain exactly one element of the range. If f is a function and x is an element of its domain, then f(x) denotes the output of f corresponding to the input x. The graph of f is the graph of the equation y = f(x).
 HSF.IF.2
Use function notation, evaluate functions for inputs in their domains, and interpret statements that use function notation in terms of a context.
 HSF.IF.3
Recognize that sequences are functions, sometimes defined recursively, whose domain is a subset of the integers. For example, the Fibonacci sequence is defined recursively by f(0) = f(1) = 1, f(n+1) = f(n) + f(n1) for n ≥ 1.
Linear, Quadratic, And Exponential Models
 HSF.LE.1
Distinguish between situations that can be modeled with linear functions and with exponential functions.
 HSF.LE.2
Construct linear and exponential functions, including arithmetic and geometric sequences, given a graph, a description of a relationship, or two inputoutput pairs (include reading these from a table).
 HSF.LE.5
Interpret the parameters in a linear or exponential function in terms of a context.
Making Inferences And Justifying Conclusions
 HSS.IC.4
Use data from a sample survey to estimate a population mean or proportion; develop a margin of error through the use of simulation models for random sampling.
 HSS.IC.1
Understand statistics as a process for making inferences about population parameters based on a random sample from that population.
Measurement And Data
 1.MD.1
Order three objects by length; compare the lengths of two objects indirectly by using a third object.
 1.MD.4
Organize, represent, and interpret data with up to three categories; ask and answer questions about the total number of data points, how many in each category, and how many more or less are in one category than in another.
 1.MD.3
Tell and write time in hours and halfhours using analog and digital clocks.
 2.MD.1
Measure the length of an object by selecting and using appropriate tools such as rulers, yardsticks, meter sticks, and measuring tapes.
 2.MD.2
Measure the length of an object twice, using length units of different lengths for the two measurements; describe how the two measurements relate to the size of the unit chosen.
 2.MD.3
Estimate lengths using units of inches, feet, centimeters, and meters.
 2.MD.4
Measure to determine how much longer one object is than another, expressing the length difference in terms of a standard length unit.
 2.MD.5
Use addition and subtraction within 100 to solve word problems involving lengths that are given in the same units, e.g., by using drawings (such as drawings of rulers) and equations with a symbol for the unknown number to represent the problem.
 2.MD.6
Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the numbers 0, 1, 2, ..., and represent wholenumber sums and differences within 100 on a number line diagram.
 2.MD.10
Draw a picture graph and a bar graph (with singleunit scale) to represent a data set with up to four categories. Solve simple put together, takeapart, and compare problems4 using information presented in a bar graph.
 2.MD.9
Generate measurement data by measuring lengths of several objects to the nearest whole unit, or by making repeated measurements of the same object. Show the measurements by making a line plot, where the horizontal scale is marked off in wholenumber units.
 2.MD.7
Tell and write time from analog and digital clocks to the nearest five minutes, using a.m. and p.m.
 2.MD.8
Solve word problems involving dollar bills, quarters, dimes, nickels, and pennies, using $ and ¢ symbols appropriately. Example: If you have 2 dimes and 3 pennies, how many cents do you have?
 3.MD.8
Solve real world and mathematical problems involving perimeters of polygons, including finding the perimeter given the side lengths, finding an unknown side length, and exhibiting rectangles with the same perimeter and different areas or with the same area and different perimeters.
 3.MD.5
Recognize area as an attribute of plane figures and understand concepts of area measurement.
 3.MD.6
Measure areas by counting unit squares (square cm, square m, square in, square ft, and improvised units).
 3.MD.7
Relate area to the operations of multiplication and addition.
 3.MD.3
Draw a scaled picture graph and a scaled bar graph to represent a data set with several categories. Solve one and twostep “how many more” and “how many less” problems using information presented in scaled bar graphs. For example, draw a bar graph in which each square in the bar graph might represent 5 pets.
 3.MD.1
Tell and write time to the nearest minute and measure time intervals in minutes. Solve word problems involving addition and subtraction of time intervals in minutes, e.g., by representing the problem on a number line diagram.
 3.MD.2
Measure and estimate liquid volumes and masses of objects using standard units of grams (g), kilograms (kg), and liters (l).6 Add, subtract, multiply, or divide to solve onestep word problems involving masses or volumes that are given in the same units, e.g., by using drawings (such as a beaker with a measurement scale) to represent the problem.7
 4.MD.5
Recognize angles as geometric shapes that are formed wherever two rays share a common endpoint, and understand concepts of angle measurement:
 4.MD.6
Measure angles in wholenumber degrees using a protractor. Sketch angles of specified measure.
 4.MD.7
Recognize angle measure as additive. When an angle is decomposed into nonoverlapping parts, the angle measure of the whole is the sum of the angle measures of the parts. Solve addition and subtraction problems to find unknown angles on a diagram in real world and mathematical problems, e.g., by using an equation with a symbol for the unknown angle measure.
 4.MD.4
Make a line plot to display a data set of measurements in fractions of a unit (1/2, 1/4, 1/8). Solve problems involving addition and subtraction of fractions by using information presented in line plots. For example, from a line plot find and interpret the difference in length between the longest and shortest specimens in an insect collection.
 4.MD.1
Know relative sizes of measurement units within one system of units including km, m, cm; kg, g; lb, oz.; l, ml; hr, min, sec. Within a single system of measurement, express measurements in a larger unit in terms of a smaller unit. Record measurement equivalents in a two column table. For example, know that 1 ft is 12 times as long as 1 in. Express the length of a 4 ft snake as 48 in. Generate a conversion table for feet and inches listing the number pairs (1, 12), (2, 24), (3, 36), ...
 4.MD.2
Use the four operations to solve word problems involving distances, intervals of time, liquid volumes, masses of objects, and money, including problems involving simple fractions or decimals, and problems that require expressing measurements given in a larger unit in terms of a smaller unit. Represent measurement quantities using diagrams such as number line diagrams that feature a measurement scale.
 4.MD.3
Apply the area and perimeter formulas for rectangles in real world and mathematical problems. For example, find the width of a rectangular room given the area of the flooring and the length, by viewing the area formula as a multiplication equation with an unknown factor.
 5.MD.1
Convert among differentsized standard measurement units within a given measurement system (e.g., convert 5 cm to 0.05 m), and use these conversions in solving multistep, real world problems.
 5.MD.3
Recognize volume as an attribute of solid figures and understand concepts of volume measurement.
 5.MD.4
Measure volumes by counting unit cubes, using cubic cm, cubic in, cubic ft, and improvised units.
 5.MD.5
Relate volume to the operations of multiplication and addition and solve real world and mathematical problems involving volume.
 5.MD.2
Make a line plot to display a data set of measurements in fractions of a unit (1/2, 1/4, 1/8). Use operations on fractions for this grade to solve problems involving information presented in line plots. For example, given different measurements of liquid in identical beakers, find the amount of liquid each beaker would contain if the total amount in all the beakers were redistributed equally.
 K.MD.3
Classify objects into given categories; count the numbers of objects in each category and sort the categories by count.3
 K.MD.1
Describe measurable attributes of objects, such as length or weight. Describe several measurable attributes of a single object.
 K.MD.2
Directly compare two objects with a measurable attribute in common, to see which object has “more of”/“less of” the attribute, and describe the difference. For example, directly compare the heights of two children and describe one child as taller/shorter.
Modeling With Geometry
 HSG.MG.1
Use geometric shapes, their measures, and their properties to describe objects (e.g., modeling a tree trunk or a human torso as a cylinder).
Number And Operations In Base Ten
 1.NBT.1
Count to 120, starting at any number less than 120. In this range, read and write numerals and represent a number of objects with a written numeral.
 1.NBT.2
Understand that the two digits of a twodigit number represent amounts of tens and ones. Understand the following as special cases:
 1.NBT.3
Compare two twodigit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols >, =, and <.
 1.NBT.4
Add within 100, including adding a twodigit number and a onedigit number, and adding a twodigit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding twodigit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.
 1.NBT.5
Given a twodigit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.
 1.NBT.6
Subtract multiples of 10 in the range 1090 from multiples of 10 in the range 1090 (positive or zero differences), using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.
 2.NBT.1
Understand that the three digits of a threedigit number represent amounts of hundreds, tens, and ones; e.g., 706 equals 7 hundreds, 0 tens, and 6 ones. Understand the following as special cases:
 2.NBT.2
Count within 1000; skipcount by 5s, 10s, and 100s.
 2.NBT.3
Read and write numbers to 1000 using baseten numerals, number names, and expanded form.
 2.NBT.4
Compare two threedigit numbers based on meanings of the hundreds, tens, and ones digits, using >, =, and < symbols to record the results of comparisons.
 2.NBT.5
Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.
 2.NBT.6
Add up to four twodigit numbers using strategies based on place value and properties of operations.
 2.NBT.7
Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
 2.NBT.8
Mentally add 10 or 100 to a given number 100–900, and mentally subtract 10 or 100 from a given number 100–900.
 2.NBT.9
Explain why addition and subtraction strategies work, using place value and the properties of operations.3
 3.NBT.1
Use place value understanding to round whole numbers to the nearest 10 or 100.
 3.NBT.2
Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.
 3.NBT.3
Multiply onedigit whole numbers by multiples of 10 in the range 10–90 (e.g., 9 × 80, 5 × 60) using strategies based on place value and properties of operations.
 5.NBT.5
Fluently multiply multidigit whole numbers using the standard algorithm.
 5.NBT.6
Find wholenumber quotients of whole numbers with up to fourdigit dividends and twodigit divisors, using strategies based on place value, the properties of operations, and/or the relationship between multiplication and division. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
 5.NBT.7
Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.
 5.NBT.1
Recognize that in a multidigit number, a digit in one place represents 10 times as much as it represents in the place to its right and 1/10 of what it represents in the place to its left.
 5.NBT.2
Explain patterns in the number of zeros of the product when multiplying a number by powers of 10, and explain patterns in the placement of the decimal point when a decimal is multiplied or divided by a power of 10. Use wholenumber exponents to denote powers of 10.
 5.NBT.3
Read, write, and compare decimals to thousandths.
 5.NBT.4
Use place value understanding to round decimals to any place.
 K.NBT.1
Compose and decompose numbers from 11 to 19 into ten ones and some further ones, e.g., by using objects or drawings, and record each composition or decomposition by a drawing or equation (e.g., 18 = 10 + 8); understand that these numbers are composed of ten ones and one, two, three, four, five, six, seven, eight, or nine ones.
 4.NBT.1
Recognize that in a multidigit whole number, a digit in one place represents ten times what it represents in the place to its right. For example, recognize that 700 ÷ 70 = 10 by applying concepts of place value and division.
 4.NBT.2
Read and write multidigit whole numbers using baseten numerals, number names, and expanded form. Compare two multidigit numbers based on meanings of the digits in each place, using >, =, and < symbols to record the results of comparisons.
 4.NBT.3
Use place value understanding to round multidigit whole numbers to any place.
 4.NBT.4
Fluently add and subtract multidigit whole numbers using the standard algorithm.
 4.NBT.5
Multiply a whole number of up to four digits by a onedigit whole number, and multiply two twodigit numbers, using strategies based on place value and the properties of operations. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
 4.NBT.6
Find wholenumber quotients and remainders with up to fourdigit dividends and onedigit divisors, using strategies based on place value, the properties of operations, and/or the relationship between multiplication and division. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
Number And Operations—Fractions
 5.NF.3
Interpret a fraction as division of the numerator by the denominator (a/b = a ÷ b). Solve word problems involving division of whole numbers leading to answers in the form of fractions or mixed numbers, e.g., by using visual fraction models or equations to represent the problem. For example, interpret 3/4 as the result of dividing 3 by 4, noting that 3/4 multiplied by 4 equals 3, and that when 3 wholes are shared equally among 4 people each person has a share of size 3/4. If 9 people want to share a 50pound sack of rice equally by weight, how many pounds of rice should each person get? Between what two whole numbers does your answer lie?
 5.NF.4
Apply and extend previous understandings of multiplication to multiply a fraction or whole number by a fraction.
 5.NF.5
Interpret multiplication as scaling (resizing), by:
 5.NF.6
Solve real world problems involving multiplication of fractions and mixed numbers, e.g., by using visual fraction models or equations to represent the problem.
 5.NF.7
Apply and extend previous understandings of division to divide unit fractions by whole numbers and whole numbers by unit fractions.1
 5.NF.1
Add and subtract fractions with unlike denominators (including mixed numbers) by replacing given fractions with equivalent fractions in such a way as to produce an equivalent sum or difference of fractions with like denominators. For example, 2/3 + 5/4 = 8/12 + 15/12 = 23/12. (In general, a/b + c/d = (ad + bc)/bd.)
 5.NF.2
Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases of unlike denominators, e.g., by using visual fraction models or equations to represent the problem. Use benchmark fractions and number sense of fractions
 4.NF.3
Understand a fraction a/b with a > 1 as a sum of fractions 1/b. a.
 4.NF.4
Apply and extend previous understandings of multiplication to multiply a fraction by a whole number.
 4.NF.1
Explain why a fraction a/b is equivalent to a fraction (n × a)/(n × b) by using visual fraction models, with attention to how the number and size of the parts differ even though the two fractions themselves are the same size. Use this principle to recognize and generate equivalent fractions.
 4.NF.2
Compare two fractions with different numerators and different denominators, e.g., by creating common denominators or numerators, or by comparing to a benchmark fraction such as 1/2. Recognize that comparisons are valid only when the two fractions refer to the same whole. Record the results of comparisons with symbols >, =, or <, and justify the conclusions, e.g., by using a visual fraction model.
 4.NF.6
Use decimal notation for fractions with denominators 10 or 100. For example, rewrite 0.62 as 62/100; describe a length as 0.62 meters; locate 0.62 on a number line diagram.
 4.NF.7
Compare two decimals to hundredths by reasoning about their size. Recognize that comparisons are valid only when the two decimals refer to the same whole. Record the results of comparisons with the symbols >, =, or <, and justify the conclusions, e.g., by using a visual model.
Operations And Algebraic Thinking
 1.OA.5
Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).
 1.OA.6
Add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Use strategies such as counting on; making ten (e.g., 8 + 6 = 8 + 2 + 4 = 10 + 4 = 14); decomposing a number leading to a ten (e.g., 13 – 4 = 13 – 3 – 1 = 10 – 1 = 9); using the relationship between addition and subtraction (e.g., knowing that 8 + 4 = 12, one knows 12 – 8 = 4); and creating equivalent but easier or known sums (e.g., adding 6 + 7 by creating the known equivalent 6 + 6 + 1 = 12 + 1 = 13).
 1.OA.1
Use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.2
 1.OA.2
Solve word problems that call for addition of three whole numbers whose sum is less than or equal to 20, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem.
 1.OA.3
Apply properties of operations as strategies to add and subtract.3 Examples: If 8 + 3 = 11 is known, then 3 + 8 = 11 is also known. (Commutative property of addition.) To add 2 + 6 + 4, the second two numbers can be added to make a ten, so 2 + 6 + 4 = 2 + 10 = 12. (Associative property of addition.)
 1.OA.4
Understand subtraction as an unknownaddend problem. For example, subtract 10 – 8 by finding the number that makes 10 when added to 8.
 1.OA.7
Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. For example, which of the following equations are true and which are false? 6 = 6, 7 = 8 – 1, 5 + 2 = 2 + 5, 4 + 1 = 5 + 2.
 1.OA.8
Determine the unknown whole number in an addition or subtraction equation relating three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 + ? = 11, 5 = _ – 3, 6 + 6 = _.
 2.OA.2
Fluently add and subtract within 20 using mental strategies.2 By end of Grade 2, know from memory all sums of two onedigit numbers.
 2.OA.1
Use addition and subtraction within 100 to solve one and twostep word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.1
 2.OA.3
Determine whether a group of objects (up to 20) has an odd or even number of members, e.g., by pairing objects or counting them by 2s; write an equation to express an even number as a sum of two equal addends.
 2.OA.4
Use addition to find the total number of objects arranged in rectangular arrays with up to 5 rows and up to 5 columns; write an equation to express the total as a sum of equal addends.
 3.OA.7
Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8 × 5 = 40, one knows 40 ÷ 5 = 8) or properties of operations. By the end of Grade 3, know from memory all products of two onedigit numbers.
 3.OA.1
Interpret products of whole numbers, e.g., interpret 5 × 7 as the total number of objects in 5 groups of 7 objects each. For example, describe a context in which a total number of objects can be expressed as 5 × 7.
 3.OA.2
Interpret wholenumber quotients of whole numbers, e.g., interpret 56 ÷ 8 as the number of objects in each share when 56 objects are partitioned equally into 8 shares, or as a number of shares when 56 objects are partitioned into equal shares of 8 objects each. For example, describe a context in which a number of shares or a number of groups can be expressed as 56 ÷ 8.
 3.OA.3
Use multiplication and division within 100 to solve word problems in situations involving equal groups, arrays, and measurement quantities, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.1
 3.OA.4
Determine the unknown whole number in a multiplication or division equation relating three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 × ? = 48, 5 = _ ÷ 3, 6 × 6 = ?.
 3.OA.8
Solve twostep word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.3
 3.OA.9
Identify arithmetic patterns (including patterns in the addition table or multiplication table), and explain them using properties of operations. For example, observe that 4 times a number is always even, and explain why 4 times a number can be decomposed into two equal addends.
 3.OA.5
Apply properties of operations as strategies to multiply and divide.2 Examples: If 6 × 4 = 24 is known, then 4 × 6 = 24 is also known. (Commutative property of multiplication.) 3 × 5 × 2 can be found by 3 × 5 = 15, then 15 × 2 = 30, or by 5 × 2 = 10, then 3 × 10 = 30. (Associative property of multiplication.) Knowing that 8 × 5 = 40 and 8 × 2 = 16, one can find 8 × 7 as 8 × (5 + 2) = (8 × 5) + (8 × 2) = 40 + 16 = 56. (Distributive property.)
 3.OA.6
Understand division as an unknownfactor problem. For example, find 32 ÷ 8 by finding the number that makes 32 when multiplied by 8.
 4.OA.4
Find all factor pairs for a whole number in the range 1–100. Recognize that a whole number is a multiple of each of its factors. Determine whether a given whole number in the range 1–100 is a multiple of a given onedigit number. Determine whether a given whole number in the range 1–100 is prime or composite.
 4.OA.5
Generate a number or shape pattern that follows a given rule. Identify apparent features of the pattern that were not explicit in the rule itself. For example, given the rule “Add 3” and the starting number 1, generate terms in the resulting sequence and observe that the terms appear to alternate between odd and even numbers. Explain informally why the numbers will continue to alternate in this way.
 4.OA.1
Interpret a multiplication equation as a comparison, e.g., interpret 35 = 5 × 7 as a statement that 35 is 5 times as many as 7 and 7 times as many as 5. Represent verbal statements of multiplicative comparisons as multiplication equations.
 4.OA.2
Multiply or divide to solve word problems involving multiplicative comparison, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem, distinguishing multiplicative comparison from additive comparison.1
 4.OA.3
Solve multistep word problems posed with whole numbers and having wholenumber answers using the four operations, including problems in which remainders must be interpreted. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.
 5.OA.3
Generate two numerical patterns using two given rules. Identify apparent relationships between corresponding terms. Form ordered pairs consisting of corresponding terms from the two patterns, and graph the ordered pairs on a coordinate plane. For example, given the rule “Add 3” and the starting number 0, and given the rule “Add 6” and the starting number 0, generate terms in the resulting sequences, and observe that the terms in one sequence are twice the corresponding terms in the other sequence. Explain informally why this is so.
 5.OA.1
Use parentheses, brackets, or braces in numerical expressions, and evaluate expressions with these symbols.
 5.OA.2
Write simple expressions that record calculations with numbers, and interpret numerical expressions without evaluating them. For example, express the calculation “add 8 and 7, then multiply by 2” as 2 × (8 + 7). Recognize that 3 × (18932 + 921) is three times as large as 18932 + 921, without having to calculate the indicated sum or product.
 K.OA.1
Represent addition and subtraction with objects, fingers, mental images, drawings2, sounds (e.g., claps), acting out situations, verbal explanations, expressions, or equations.
 K.OA.2
Solve addition and subtraction word problems, and add and subtract within 10, e.g., by using objects or drawings to represent the problem.
 K.OA.3
Decompose numbers less than or equal to 10 into pairs in more than one way, e.g., by using objects or drawings, and record each decomposition by a drawing or equation (e.g., 5 = 2 + 3 and 5 = 4 + 1).
 K.OA.5
Fluently add and subtract within 5.
Quantities
 HSN.Q .1
Use units as a way to understand problems and to guide the solution of multistep problems; choose and interpret units consistently in formulas; choose and interpret the scale and the origin in graphs and data displays.
 HSN.Q .2
Define appropriate quantities for the purpose of descriptive modeling.
 HSN.Q .3
Choose a level of accuracy appropriate to limitations on measurement when reporting quantities.
Ratios And Proportional Relationships
 6.RP.1
Understand the concept of a ratio and use ratio language to describe a ratio relationship between two quantities. For example, “The ratio of wings to beaks in the bird house at the zoo was 2:1, because for every 2 wings there was 1 beak.” “For every vote candidate A received, candidate C received nearly three votes.”
 6.RP.2
Understand the concept of a unit rate a/b associated with a ratio a:b with b ≠ 0, and use rate language in the context of a ratio relationship. For example, “This recipe has a ratio of 3 cups of flour to 4 cups of sugar, so there is 3/4 cup of flour for each cup of sugar.” “We paid $75 for 15 hamburgers, which is a rate of $5 per hamburger.”1
 6.RP.3
Use ratio and rate reasoning to solve realworld and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations.
 7.RP.2
Recognize and represent proportional relationships between quantities.
 7.RP.3
Use proportional relationships to solve multistep ratio and percent problems. Examples: simple interest, tax, markups and markdowns, gratuities and commissions, fees, percent increase and decrease, percent error.
Reasoning With Equations And Inequalities
 HSA.REI.10
Understand that the graph of an equation in two variables is the set of all its solutions plotted in the coordinate plane, often forming a curve (which could be a line).
 HSA.REI.11
Explain why the xcoordinates of the points where the graphs of the equations y = f(x) and y = g(x) intersect are the solutions of the equation f(x) = g(x); find the solutions approximately, e.g., using technology to graph the functions, make tables of values, or find successive approximations. Include cases where f(x) and/or g(x) are linear, polynomial, rational, absolute value, exponential, and logarithmic functions.
 HSA.REI.12
Graph the solutions to a linear inequality in two variables as a half plane (excluding the boundary in the case of a strict inequality), and graph the solution set to a system of linear inequalities in two variables as the intersection of the corresponding halfplanes.
 HSA.REI.3
Solve linear equations and inequalities in one variable, including equations with coefficients represented by letters.
 HSA.REI.4
Solve quadratic equations in one variable.
 HSA.REI.5
Prove that, given a system of two equations in two variables, replacing one equation by the sum of that equation and a multiple of the other produces a system with the same solutions.
 HSA.REI.6
Solve systems of linear equations exactly and approximately (e.g., with graphs), focusing on pairs of linear equations in two variables.
 HSA.REI.8
(+) Represent a system of linear equations as a single matrix equation in a vector variable.
 HSA.REI.1
Explain each step in solving a simple equation as following from the equality of numbers asserted at the previous step, starting from the assumption that the original equation has a solution. Construct a viable argument to justify a solution method.
 HSA.REI.2
Solve simple rational and radical equations in one variable, and give examples showing how extraneous solutions may arise.
Seeing Structure In Expressions
 HSA.SSE.1
Interpret expressions that represent a quantity in terms of its context.
 HSA.SSE.2
Use the structure of an expression to identify ways to rewrite it. For example, see x4 – y4 as (x2)2 – (y2)2, thus recognizing it as a difference of squares that can be factored as (x2 – y2)(x2 + y2).
 HSA.SSE.3
Choose and produce an equivalent form of an expression to reveal and explain properties of the quantity represented by the expression.
 HSA.SSE.4
Derive the formula for the sum of a finite geometric series (when the common ratio is not 1), and use the formula to solve problems. For example, calculate mortgage payments.
Similarity, Right Triangles, And Trigonometry
 HSG.SRT.8
Use trigonometric ratios and the Pythagorean Theorem to solve right triangles in applied problems.
 HSG.SRT.5
Use congruence and similarity criteria for triangles to solve problems and to prove relationships in geometric figures.
 HSG.SRT.1
Verify experimentally the properties of dilations given by a center and a scale factor:
 HSG.SRT.2
Given two figures, use the definition of similarity in terms of similarity transformations to decide if they are similar; explain using similarity transformations the meaning of similarity for triangles as the equality of all corresponding pairs of angles and the proportionality of all corresponding pairs of sides.
 HSG.SRT.3
Use the properties of similarity transformations to establish the AA criterion for two triangles to be similar.
Statistics And Probability
 6.SP.1
Recognize a statistical question as one that anticipates variability in the data related to the question and accounts for it in the answers. For example, “How old am I?” is not a statistical question, but “How old are the students in my school?” is a statistical question because one anticipates variability in students’ ages.
 6.SP.2
Understand that a set of data collected to answer a statistical question has a distribution which can be described by its center, spread, and overall shape.
 6.SP.3
Recognize that a measure of center for a numerical data set summarizes all of its values with a single number, while a measure of variation describes how its values vary with a single number.
 6.SP.4
Display numerical data in plots on a number line, including dot plots, histograms, and box plots.
 6.SP.5
Summarize numerical data sets in relation to their context, such as by:
 7.SP.4
Use measures of center and measures of variability for numerical data from random samples to draw informal comparative inferences about two populations. For example, decide whether the words in a chapter of a seventhgrade science book are generally longer than the words in a chapter of a fourthgrade science book.
 7.SP.5
Understand that the probability of a chance event is a number between 0 and 1 that expresses the likelihood of the event occurring. Larger numbers indicate greater likelihood. A probability near 0 indicates an unlikely event, a probability around 1/2 indicates an event that is neither unlikely nor likely, and a probability near 1 indicates a likely event.
 7.SP.6
Approximate the probability of a chance event by collecting data on the chance process that produces it and observing its longrun relative frequency, and predict the approximate relative frequency given the probability. For example, when rolling a number cube 600 times, predict that a 3 or 6 would be rolled roughly 200 times, but probably not exactly 200 times.
 7.SP.7
Develop a probability model and use it to find probabilities of events. Compare probabilities from a model to observed frequencies; if the agreement is not good, explain possible sources of the discrepancy.
 7.SP.8
Find probabilities of compound events using organized lists, tables, tree diagrams, and simulation.
 7.SP.1
Understand that statistics can be used to gain information about a population by examining a sample of the population; generalizations about a population from a sample are valid only if the sample is representative of that population. Understand that random sampling tends to produce representative samples and support valid inferences.
 7.SP.2
Use data from a random sample to draw inferences about a population with an unknown characteristic of interest. Generate multiple samples (or simulated samples) of the same size to gauge the variation in estimates or predictions. For example, estimate the mean word length in a book by randomly sampling words from the book; predict the winner of a school election based on randomly sampled survey data. Gauge how far off the estimate or prediction might be.
 8.SP.1
Construct and interpret scatter plots for bivariate measurement data to investigate patterns of association between two quantities. Describe patterns such as clustering, outliers, positive or negative association, linear association, and nonlinear association.
 8.SP.3
Use the equation of a linear model to solve problems in the context of bivariate measurement data, interpreting the slope and intercept. For example, in a linear model for a biology experiment, interpret a slope of 1.5 cm/hr as meaning that an additional hour of sunlight each day is associated with an additional 1.5 cm in mature plant height.
 8.SP.4
Understand that patterns of association can also be seen in bivariate categorical data by displaying frequencies and relative frequencies in a twoway table. Construct and interpret a twoway table summarizing data on two categorical variables collected from the same subjects. Use relative frequencies calculated for rows or columns to describe possible association between the two variables. For example, collect data from students in your class on whether or not they have a curfew on school nights and whether or not they have assigned chores at home. Is there evidence that those who have a curfew also tend to have chores?
The Number System
 6.NS.1
Interpret and compute quotients of fractions, and solve word problems involving division of fractions by fractions, e.g., by using visual fraction models and equations to represent the problem. For example, create a story context for (2/3) ÷ (3/4) and use a visual fraction model to show the quotient; use the relationship between multiplication and division to explain that (2/3) ÷ (3/4) = 8/9 because 3/4 of 8/9 is 2/3. (In general, (a/b) ÷ (c/d) = ad/bc.) How much chocolate will each person get if 3 people share 1/2 lb of chocolate equally? How many 3/4cup servings are in 2/3 of a cup of yogurt? How wide is a rectangular strip of land with length 3/4 mi and area 1/2 square mi?
 6.NS.5
Understand that positive and negative numbers are used together to describe quantities having opposite directions or values (e.g., temperature above/below zero, elevation above/below sea level, credits/debits, positive/negative electric charge); use positive and negative numbers to represent quantities in realworld contexts, explaining the meaning of 0 in each situation.
 6.NS.6
Understand a rational number as a point on the number line. Extend number line diagrams and coordinate axes familiar from previous grades to represent points on the line and in the plane with negative number coordinates.
 6.NS.7
Understand ordering and absolute value of rational numbers.
 6.NS.8
Solve realworld and mathematical problems by graphing points in all four quadrants of the coordinate plane. Include use of coordinates and absolute value to find distances between points with the same first coordinate or the same second coordinate.
 6.NS.2
Fluently divide multidigit numbers using the standard algorithm.
 6.NS.3
Fluently add, subtract, multiply, and divide multidigit decimals using the standard algorithm for each operation.
 6.NS.4
Find the greatest common factor of two whole numbers less than or equal to 100 and the least common multiple of two whole numbers less than or equal to 12. Use the distributive property to express a sum of two whole numbers 1–100 with a common factor as a multiple of a sum of two whole numbers with no common factor. For example, express 36 + 8 as 4 (9 + 2).
 7.NS.1
Apply and extend previous understandings of addition and subtraction to add and subtract rational numbers; represent addition and subtraction on a horizontal or vertical number line diagram.
 7.NS.2
Apply and extend previous understandings of multiplication and division and of fractions to multiply and divide rational numbers.
 7.NS.3
Solve realworld and mathematical problems involving the four operations with rational numbers.
 8.NS.1
Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion which repeats eventually into a rational number.
 8.NS.2
Use rational approximations of irrational numbers to compare the size of irrational numbers, locate them approximately on a number line diagram, and estimate the value of expressions (e.g., π2). For example, by truncating the decimal expansion of √2, show that √2 is between 1 and 2, then between 1.4 and 1.5, and explain how to continue on to get better approximations.
The Real Number System
 HSN.RN.2
Rewrite expressions involving radicals and rational exponents using the properties of exponents.
Vector And Matrix Quantities
 HSN.VM.7
(+) Multiply matrices by scalars to produce new matrices, e.g., as when all of the payoffs in a game are doubled.
 HSN.VM.8
(+) Add, subtract, and multiply matrices of appropriate dimensions.
 HSN.VM.9
(+) Understand that, unlike multiplication of numbers, matrix multiplication for square matrices is not a commutative operation, but still satisfies the associative and distributive properties.
Key Standards Supported
Language
 L.2.1
Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
 L.2.1a
Use collective nouns (e.g., group).
 L.2.1b
Form and use frequently occurring irregular plural nouns (e.g., feet, children, teeth, mice, fish).
 L.2.1c
Use reflexive pronouns (e.g., myself, ourselves).
 L.2.1d
Form and use the past tense of frequently occurring irregular verbs (e.g., sat, hid, told).
 L.2.1e
Use adjectives and adverbs, and choose between them depending on what is to be modified.
 L.2.1f
Produce, expand, and rearrange complete simple and compound sentences (e.g., The boy watched the movie; The little boy watched the movie; The action movie was watched by the little boy).
 L.2.2
Demonstrate command of the conventions of standard English capitalization, punctuation, and spelling when writing.
 L.2.2a
Capitalize holidays, product names, and geographic names.
 L.2.2b
Use commas in greetings and closings of letters.
 L.2.2c
Use an apostrophe to form contractions and frequently occurring possessives.
 L.2.2d
Generalize learned spelling patterns when writing words (e.g., cage → badge; boy → boil).
 L.2.2e
Consult reference materials, including beginning dictionaries, as needed to check and correct spellings.
 L.2.3
Use knowledge of language and its conventions when writing, speaking, reading, or listening.
 L.2.3a
Compare formal and informal uses of English.
 L.2.4
Determine or clarify the meaning of unknown and multiplemeaning words and phrases based on grade 2 reading and content, choosing flexibly from an array of strategies.
 L.2.4a
Use sentencelevel context as a clue to the meaning of a word or phrase.
 L.2.4b
Determine the meaning of the new word formed when a known prefix is added to a known word (e.g., happy/unhappy, tell/retell).
 L.2.4c
Use a known root word as a clue to the meaning of an unknown word with the same root (e.g., addition, additional).
 L.2.4d
Use knowledge of the meaning of individual words to predict the meaning of compound words (e.g., birdhouse, lighthouse, housefly; bookshelf, notebook, bookmark).
 L.2.4e
Use glossaries and beginning dictionaries, both print and digital, to determine or clarify the meaning of words and phrases.
 L.2.5
Demonstrate understanding of figurative language, word relationships and nuances in word meanings.
 L.2.5b
Distinguish shades of meaning among closely related verbs (e.g., toss, throw, hurl) and closely related adjectives (e.g., thin, slender, skinny, scrawny).
 L.2.6
Use words and phrases acquired through conversations, reading and being read to, and responding to texts, including using adjectives and adverbs to describe (e.g., When other kids are happy that makes me happy).
 L2.5a
Identify reallife connections between words and their use (e.g., describe foods that are spicy or juicy).
 L.3.1
Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
 L.3.1a
Explain the function of nouns, pronouns, verbs, adjectives, and adverbs in general and their functions in particular sentences.
 L.3.1b
Form and use regular and irregular plural nouns.
 L.3.1c
Use abstract nouns (e.g., childhood).
 L.3.1d
Form and use regular and irregular verbs.
 L.3.1e
Form and use the simple (e.g., I walked; I walk; I will walk) verb tenses.
 L.3.1f
Ensure subjectverb and pronounantecedent agreement.*
 L.3.1g
Form and use comparative and superlative adjectives and adverbs, and choose between them depending on what is to be modified.
 L.3.1h
Use coordinating and subordinating conjunctions.
 L.3.1i
Produce simple, compound, and complex sentences.
 L.3.2
Demonstrate command of the conventions of standard English capitalization, punctuation, and spelling when writing.
 L.3.2a
Capitalize appropriate words in titles.
 L.3.2b
Use commas in addresses.
 L.3.2d
Form and use possessives.
 L.3.2e
Use conventional spelling for highfrequency and other studied words and for adding suffixes to base words (e.g., sitting, smiled, cries, happiness).
 L.3.2f
Use spelling patterns and generalizations (e.g., word families, positionbased spellings, syllable patterns, ending rules, meaningful word parts) in writing words.
 L.3.2g
Consult reference materials, including beginning dictionaries, as needed to check and correct spellings.
 L3.2c
Use commas and quotation marks in dialogue.
 L.3.3
Use knowledge of language and its conventions when writing, speaking, reading, or listening.
 L.3.3a
Choose words and phrases for effect.*
 L.3.3b
Recognize and observe differences between the conventions of spoken and written standard English.
 L.3.4
Determine or clarify the meaning of unknown and multiplemeaning word and phrases based on grade 3 reading and content, choosing flexibly from a range of strategies.
 L.3.4a
Use sentencelevel context as a clue to the meaning of a word or phrase.
 L.3.4b
Determine the meaning of the new word formed when a known affix is added to a known word (e.g., agreeable/disagreeable, comfortable/uncomfortable, care/careless, heat/preheat).
 L.3.4c
Use a known root word as a clue to the meaning of an unknown word with the same root (e.g., company, companion).
 L.3.4d
Use glossaries or beginning dictionaries, both print and digital, to determine or clarify the precise meaning of key words and phrases.
 L.3.5
Demonstrate understanding of figurative language, word relationships and nuances in word meanings.
 L.3.5a
Distinguish the literal and nonliteral meanings of words and phrases in context (e.g., take steps).
 L.3.5b
Identify reallife connections between words and their use (e.g., describe people who are friendly or helpful).
 L.3.5c
Distinguish shades of meaning among related words that describe states of mind or degrees of certainty (e.g., knew, believed, suspected, heard, wondered).
 L.3.6
Acquire and use accurately gradeappropriate conversational, general academic, and domainspecific words and phrases, including those that signal spatial and temporal relationships (e.g., After dinner that night we went looking for them).
 L.4.1
Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
 L.4.1a
Use relative pronouns (who, whose, whom, which, that) and relative adverbs (where, when, why).
 L.4.1b
Form and use the progressive (e.g., I was walking; I am walking; I will be walking) verb tenses.
 L.4.1c
Use modal auxiliaries (e.g., can, may, must) to convey various conditions.
 L.4.1d
Order adjectives within sentences according to conventional patterns (e.g., a small red bag rather than a red small bag).
 L.4.1e
Form and use prepositional phrases.
 L.4.1f
Produce complete sentences, recognizing and correcting inappropriate fragments and runons.*
 L.4.1g
Correctly use frequently confused words (e.g., to, too, two; there, their).*
 L.4.2
Demonstrate command of the conventions of standard English capitalization, punctuation, and spelling when writing.
 L.4.2a
Use correct capitalization.
 L.4.2b
Use commas and quotation marks to mark direct speech and quotations from a text.
 L.4.2c
Use a comma before a coordinating conjunction in a compound sentence.
 L.4.2d
Spell gradeappropriate words correctly, consulting references as needed.
 L.4.3
Use knowledge of language and its conventions when writing, speaking, reading, or listening.
 L.4.3a
Choose words and phrases to convey ideas precisely.*
 L.4.3b
Choose punctuation for effect.*
 L.4.3c
Differentiate between contexts that call for formal English (e.g., presenting ideas) and situations where informal discourse is appropriate (e.g., smallgroup discussion).
 L.4.4
Determine or clarify the meaning of unknown and multiplemeaning words and phrases based on grade 4 reading and content, choosing flexibly from a range of strategies.
 L.4.4a
Use context (e.g., definitions, examples, or restatements in text) as a clue to the meaning of a word or phrase.
 L.4.4b
Use common, gradeappropriate Greek and Latin affixes and roots as clues to the meaning of a word (e.g., telegraph, photograph, autograph).
 L.4.4c
Consult reference materials (e.g., dictionaries, glossaries, thesauruses), both print and digital, to find the pronunciation and determine or clarify the precise meaning of key words and phrases.
 L.4.5
Demonstrate understanding of figurative language, word relationships, and nuances in word meanings.
 L.4.5a
Explain the meaning of simple similes and metaphors (e.g., as pretty as a picture) in context.
 L.4.5b
Recognize and explain the meaning of common idioms, adages, and proverbs.
 L.4.5c
Demonstrate understanding of words by relating them to their opposites (antonyms) and to words with similar but not identical meanings (synonyms).
 L.4.6
Acquire and use accurately gradeappropriate general academic and domainspecific words and phrases, including those that signal precise actions, emotions, or states of being (e.g., quizzed, whined, stammered) and that are basic to a particular topic (e.g., wildlife, conservation, and endangered when discussing animal preservation).
 L.5.1
Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
 L.5.2
Demonstrate command of the conventions of standard English capitalization, punctuation, and spelling when writing.
 L.5.3
Use knowledge of language and its conventions when writing, speaking, reading, or listening.
 L.5.3a
Expand, combine, and reduce sentences for meaning, reader/listener interest, and style.
 L.5.3b
Compare and contrast the varieties of English (e.g., dialects, registers) used in stories, dramas, or poems.
 L.5.4
Determine or clarify the meaning of unknown and multiplemeaning words and phrases based on grade 5 reading and content, choosing flexibly from a range of strategies.
 L.5.4a
Use context (e.g., cause/effect relationships and comparisons in text) as a clue to the meaning of a word or phrase.
 L.5.4b
Use common, gradeappropriate Greek and Latin affixes and roots as clues to the meaning of a word (e.g., photograph, photosynthesis).
 L.5.4c
Consult reference materials (e.g., dictionaries, glossaries, thesauruses), both print and digital, to find the pronunciation and determine or clarify the precise meaning of key words and phrases.
 L.5.5
Demonstrate understanding of figurative language, word relationships, and nuances in word meanings.
 L.5.5a
Interpret figurative language, including similes and metaphors, in context.
 L.5.5b
Recognize and explain the meaning of common idioms, adages, and proverbs.
 L.5.5c
Use the relationship between particular words (e.g., synonyms, antonyms, homographs) to better understand each of the words.
 L.5.6
Acquire and use accurately gradeappropriate general academic and domainspecific words and phrases, including those that signal contrast, addition, and other logical relationships (e.g., however, although, nevertheless, similarly, moreover, in addition).
 L.6.1
Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
 L.6.1.A
Ensure that pronouns are in the proper case (subjective, objective, possessive).
 L.6.1.B
Use intensive pronouns (e.g., myself, ourselves).
 L.6.1.C
Recognize and correct inappropriate shifts in pronoun number and person.
 L.6.1.D
Recognize and correct vague pronouns (i.e., ones with unclear or ambiguous antecedents).
 L.6.1.E
Recognize variations from standard English in their own and others' writing and speaking, and identify and use strategies to improve expression in conventional language.
 L.6.2
Demonstrate command of the conventions of standard English capitalization, punctuation, and spelling when writing.
 L.6.2.A
Use punctuation (commas, parentheses, dashes) to set off nonrestrictive/parenthetical elements.*
 L.6.2.B
Spell correctly.
 L.6.3
Use knowledge of language and its conventions when writing, speaking, reading, or listening.
 L.6.3.A
Vary sentence patterns for meaning, reader/listener interest, and style.
 L.6.3.B
Maintain consistency in style and tone.
 L.6.4
Determine or clarify the meaning of unknown and multiplemeaning words and phrases based on grade 6 reading and content, choosing flexibly from a range of strategies.
 L.6.4.A
Use context (e.g., the overall meaning of a sentence or paragraph; a word's position or function in a sentence) as a clue to the meaning of a word or phrase.
 L.6.4.B
Use common, gradeappropriate Greek or Latin affixes and roots as clues to the meaning of a word (e.g., audience, auditory, audible).
 L.6.4.C
Consult reference materials (e.g., dictionaries, glossaries, thesauruses), both print and digital, to find the pronunciation of a word or determine or clarify its precise meaning or its part of speech.
 L.6.4.D
Verify the preliminary determination of the meaning of a word or phrase (e.g., by checking the inferred meaning in context or in a dictionary).
 L.6.5
Demonstrate understanding of figurative language, word relationships, and nuances in word meanings.
 L.6.5.A
Interpret figures of speech (e.g., personification) in context.
 L.6.5.B
Use the relationship between particular words (e.g., cause/effect, part/whole, item/category) to better understand each of the words.
 L.6.5.C
Distinguish among the connotations (associations) of words with similar denotations (definitions) (e.g., stingy, scrimping, economical, unwasteful, thrifty).
 L.6.6
Acquire and use accurately gradeappropriate general academic and domainspecific words and phrases; gather vocabulary knowledge when considering a word or phrase important to comprehension or expression.
 L.7.1
Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
 L.7.1a
Explain the function of phrases and clauses in general and their function in specific sentences.
 L.7.1b
Choose among simple, compound, complex, and compoundcomplex sentences to signal differing relationships among ideas.
 L.7.1c
Place phrases and clauses within a sentence, recognizing and correcting misplaced and dangling modifiers.*
 L.7.2
Demonstrate command of the conventions of standard English capitalization, punctuation, and spelling when writing.
 L.7.2a
Use a comma to separate coordinate adjectives (e.g., It was a fascinating, enjoyable movie but not He wore an old[,] green shirt).
 L.7.2b
Spell correctly.
 L.7.3
Use knowledge of language and its conventions when writing, speaking, reading, or listening.
 L.7.3a
Choose language that expresses ideas precisely and concisely, recognizing and eliminating wordiness and redundancy.*
 L.7.4
Determine or clarify the meaning of unknown and multiplemeaning words and phrases based on grade 7 reading and content, choosing flexibly from a range of strategies.
 L.7.4a
Use context (e.g., the overall meaning of a sentence or paragraph; a word’s position or function in a sentence) as a clue to the meaning of a word or phrase.
 L.7.4b
Use common, gradeappropriate Greek or Latin affixes and roots as clues to the meaning of a word (e.g., belligerent, bellicose, rebel).
 L.7.4c
Consult general and specialized reference materials (e.g., dictionaries, glossaries, thesauruses), both print and digital, to find the pronunciation of a word or determine or clarify its precise meaning or its part of speech.
 L.7.4d
Verify the preliminary determination of the meaning of a word or phrase (e.g., by checking the inferred meaning in context or in a dictionary).
 L.7.5
Demonstrate understanding of figurative language, word relationships, and nuances in word meanings.
 L.7.5a
Interpret figures of speech (e.g., literary, biblical, and mythological allusions) in context.
 L.7.5b
Use the relationship between particular words (e.g., synonym/antonym, analogy) to better understand each of the words.
 L.7.5c
Distinguish among the connotations (associations) of words with similar denotations (definitions) (e.g., refined, respectful, polite, diplomatic, condescending).
 L.7.6
Acquire and use accurately gradeappropriate general academic and domainspecific words and phrases; gather vocabulary knowledge when considering a word or phrase important to comprehension or expression.
 L.8.1
Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
 L.8.1a
Explain the function of verbals (gerunds, participles, infinitives) in general and their function in particular sentences.
 L.8.1b
Form and use verbs in the active and passive voice.
 L.8.1c
Form and use verbs in the indicative, imperative, interrogative, conditional, and subjunctive mood.
 L.8.1d
Recognize and correct inappropriate shifts in verb voice and mood.*
 L.8.2
Demonstrate command of the conventions of standard English capitalization, punctuation, and spelling when writing.
 L.8.2a
Use punctuation (comma, ellipsis, dash) to indicate a pause or break.
 L.8.2b
Use an ellipsis to indicate an omission.
 L.8.2c
Spell correctly.
 L.8.3
Use knowledge of language and its conventions when writing, speaking, reading, or listening.
 L.8.3a
Use verbs in the active and passive voice and in the conditional and subjunctive mood to achieve particular effects (e.g., emphasizing the actor or the action; expressing uncertainty or describing a state contrary to fact).
 L.8.4
Determine or clarify the meaning of unknown and multiplemeaning words or phrases based on grade 8 reading and content, choosing flexibly from a range of strategies.
 L.8.4a
Use context (e.g., the overall meaning of a sentence or paragraph; a word’s position or function in a sentence) as a clue to the meaning of a word or phrase.
 L.8.4b
Use common, gradeappropriate Greek or Latin affixes and roots as clues to the meaning of a word (e.g., precede, recede, secede).
 L.8.4c
Consult general and specialized reference materials (e.g., dictionaries, glossaries, thesauruses), both print and digital, to find the pronunciation of a word or determine or clarify its precise meaning or its part of speech.
 L.8.4d
Verify the preliminary determination of the meaning of a word or phrase (e.g., by checking the inferred meaning in context or in a dictionary).
 L.8.5
Demonstrate understanding of figurative language, word relationships, and nuances in word meanings.
 L.8.5a
Interpret figures of speech (e.g. verbal irony, puns) in context.
 L.8.5b
Use the relationship between particular words to better understand each of the words.
 L.8.5c
Distinguish among the connotations (associations) of words with similar denotations (definitions) (e.g., bullheaded, willful, firm, persistent, resolute).
 L.8.6
Acquire and use accurately gradeappropriate general academic and domainspecific words and phrases; gather vocabulary knowledge when considering a word or phrase important to comprehension or expression.
 L.910.1
Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
 L.910.1a
Use parallel structure.*
 L.910.1b
Use various types of phrases (noun, verb, adjectival, adverbial, participial, prepositional, absolute) and clauses (independent, dependent; noun, relative, adverbial) to convey specific meanings and add variety and interest to writing or presentations.
 L.910.2
Demonstrate command of the conventions of standard English capitalization, punctuation, and spelling when writing.
 L.910.2a
Use a semicolon (and perhaps a conjunctive adverb) to link two or more closely related independent clauses.
 L.910.2b
Use a colon to introduce a list or quotation.
 L.910.2c
Spell correctly.
 L.910.3
Apply knowledge of language to understand how language functions in different contexts, to make effective choices for meaning or style, and to comprehend more fully when reading or listening.
 L.910.3a
Write and edit work so that it conforms to the guidelines in a style manual (e.g., MLA Handbook, Turabian’s Manual for Writers) appropriate for the discipline and writing type.
 L.910.4
Determine or clarify the meaning of unknown and multiplemeaning words and phrases based on grades 9–10 reading and content, choosing flexibly from a range of strategies.
 L.910.4a
Use context (e.g., the overall meaning of a sentence, paragraph, or text; a word’s position or function in a sentence) as a clue to the meaning of a word or phrase.
 L.910.4b
Identify and correctly use patterns of word changes that indicate different meanings or parts of speech (e.g., analyze, analysis, analytical; advocate, advocacy).
 L.910.4c
Consult general and specialized reference materials (e.g., dictionaries, glossaries, thesauruses), both print and digital, to find the pronunciation of a word or determine or clarify its precise meaning, its part of speech, or its etymology.
 L.910.4d
Verify the preliminary determination of the meaning of a word or phrase (e.g., by checking the inferred meaning in context or in a dictionary).
 L.910.5
Demonstrate understanding of figurative language, word relationships, and nuances in word meanings.
 L.910.5a
Interpret figures of speech (e.g., euphemism, oxymoron) in context and analyze their role in the text.
 L.910.5b
Analyze nuances in the meaning of words with similar denotations.
 L.910.6
Acquire and use accurately general academic and domainspecific words and phrases, sufficient for reading, writing, speaking, and listening at the college and career readiness level; demonstrate independence in gathering vocabulary knowledge when considering a word or phrase important to comprehension or expression.
Key Standards Supported
Biological Evolution: Unity and Diversity
 2LS41
Make observations of plants and animals to compare the diversity of life in different habitats.
 3LS41
Analyze and interpret data from fossils to provide evidence of the organisms and the environments in which they lived long ago.
 3LS42
Use evidence to construct an explanation for how the variations in characteristics among individuals of the same species may provide advantages in surviving, finding mates, and reproducing.
 3LS43
Construct an argument with evidence that in a particular habitat some organisms can survive well, some survive less well, and some cannot survive at all.
Earth and Human Activity
 4ESS31
Obtain and combine information to describe that energy and fuels are derived from natural resources and their uses affect the environment.
 5ESS31
Obtain and combine information about ways individual communities use science ideas to protect the Earth’s resources and environment.
Earth’s Place in the Universe
 2ESS11
Use information from several sources to provide evidence that Earth events can occur quickly or slowly.
 4ESS11
Identify evidence from patterns in rock formations and fossils in rock layers to support an explanation for changes in a landscape over time.
 5ESS11
Support an argument that differences in the apparent brightness of the sun compared to other stars is due to their relative distances from Earth.
 5ESS12
Represent data in graphical displays to reveal patterns of daily changes in length and direction of shadows, day and night, and the seasonal appearance of some stars in the night sky.
Earth’s Systems
 2ESS21
Compare multiple solutions designed to slow or prevent wind or water from changing the shape of the land.
 2ESS23
Obtain information to identify where water is found on Earth and that it can be solid or liquid.
 3ESS21
Represent data in tables and graphical displays to describe typical weather conditions expected during a particular season.
 3ESS22
Obtain and combine information to describe climates in different regions of the world.
Ecosystems: Interactions, Energy, and Dynamics
 3LS21
Construct an argument that some animals form groups that help members survive.
Energy
 4PS31
Use evidence to construct an explanation relating the speed of an object to the energy of that object.
 4PS32
Make observations to provide evidence that energy can be transferred from place to place by sound, light, heat, and electric currents.
 4PS33
Ask questions and predict outcomes about the changes in energy that occur when objects collide.
 5PS31
Use models to describe that energy in animals’ food (used for body repair, growth, motion, and to maintain body warmth) was once energy from the sun.
From Molecules to Organisms: Structures and Processes
 3LS12
Use evidence to support the explanation that traits can be influenced by the environment.
 4LS11
Construct an argument that plants and animals have internal and external structures that function to support survival, growth, behavior, and reproduction.
 4LS12
Use a model to describe that animals’ receive different types of information through their senses, process the information in their brain, and respond to the information in different ways.
 5LS11
Support an argument that plants get the materials they need for growth chiefly from air and water.
Heredity: Inheritance and Variation of Traits
 3LS31
Analyze and interpret data to provide evidence that plants and animals have traits inherited from parents and that variation of these traits exists in a group of similar organisms.
 3LS32
Use evidence to support the explanation that traits can be influenced by the environment.
Matter and Its Interactions
 2PS14
Construct an argument with evidence that some changes caused by heating or cooling can be reversed and some cannot.
 5PS13
Make observations and measurements to identify materials based on their properties.
Motion and Stability: Forces and Interactions
 3PS22
Make observations and/or measurements of an object’s motion to provide evidence that a pattern can be used to predict future motion.
 3PS23
Ask questions to determine cause and effect relationships of electric or magnetic interactions between two objects not in contact with each other.
 5PS21
Support an argument that the gravitational force exerted by Earth on objects is directed down.
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