Teachers can encourage kids to keep Pre-Algebra Guide as a handy reference when they're working independently in class or doing homework. It's a basic app with no real interactivity, but students could work in pairs to quiz each other on math rules, using Pre-Algebra Guide to confirm answers.Continue reading Show less
Pre-Algebra Guide is a handy mathematics reference for middle and high school students. There are no games or other interactivity, but students who read the bite-sized explanations across the 50 swipeable pages will find thorough yet concise examples of everything from basic foundational number concepts to square roots to the Pythagorean Theorem.
Students choose from a list of concepts and carefully read text including explanations and examples. Most concepts fit on one page, but some span two. Navigation is simple with a home page symbol, back and forward buttons, and swipeable pages. Important terms or groups of numbers under discussion are highlighted by blue or red text. Titles, organizers, and questions are in purple text. Rare geometric figures are drawn with precision. Some pages require scrolling down by swiping.
It's a quick reference and not much more, which is OK. Kids can use Pre-Algebra Guide to learn mathematical concepts, but more likely they'll use it to double-check and solidify them. Many people forget math concepts every once in a while, such as how to divide fractions, or the definitions of mode or range. With this app, students won't have to search through their textbook -- in a matter of a few taps, they'll have the help they're looking for. Though text is small and there's no zoom feature, the spacing, text colors, bold formatting, and icons are used carefully to give a clear presentation.
Key Standards Supported
Expressions And Equations
Write, read, and evaluate expressions in which letters stand for numbers.
Apply the properties of operations to generate equivalent expressions.
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.
Know and apply the properties of integer exponents to generate equivalent numerical expressions. For example, 32 × 3–5 = 3–3 = 1/33 = 1/27.
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.
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.
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.
Apply the Pythagorean Theorem to determine unknown side lengths in right triangles in real-world and mathematical problems in two and three dimensions.
Apply the Pythagorean Theorem to find the distance between two points in a coordinate system.
The Number System
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 3/4-cup 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?
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 real-world contexts, explaining the meaning of 0 in each situation.
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.
Fluently divide multi-digit numbers using the standard algorithm.
Fluently add, subtract, multiply, and divide multi-digit decimals using the standard algorithm for each operation.
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).
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.
Apply and extend previous understandings of multiplication and division and of fractions to multiply and divide rational numbers.