Updated October 2014
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CK-12: Geometry

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Shape up your kids' skills with a variety of content-rich resources

Subjects & skills
Subjects
  • Math
Skills
  • Critical Thinking
Grades This grade range is a recommendation by Common Sense Education and not the developer/publisher.
5–12
Common Sense says
Not yet reviewed
Teachers say (1 Review)
Price:  Free
Platforms:  Website

Take a look inside

4 images
Resources cover a wide range of topics that are easy to search.
Among several resources, there's a listing of Common Core standards coverage.
The variety of resource types should appeal to kids with different learning styles.

How Can I Teach with This Tool?

CK-12's Geometry module includes a wide variety of resources, including reading passages, pre- and post-read activities, assessments, videos, study aids, and Web links. Topic coverage is extremely comprehensive, including Definitions and Introductions to Proof, Pythagorean Theorem, Perimeter, Circumference, Area, and a whole host of others. As with other CK-12 math modules, topics are further broken down into subtopics, so it's easy to search for resources that align to specific lessons you're teaching.

No matter what topic you're teaching, you can have your students complete the Read activities as part of a lesson wrap-up. They can work individually or in collaborative groups, but it's probably best to also review and discuss the Guided Practice answers as a whole class. The videos make for great whole-class instructional support -- you can pause to address specific concerns or address potential problem areas in more detail.

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Standards:

Key Standards Supported

Congruence

  • HSG.CO.10

    Prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180°; base angles of isosceles triangles are congruent; the segment joining midpoints of two sides of a triangle is parallel to the third side and half the length; the medians of a triangle meet at a point.

Geometric Measurement And Dimension

  • HSG.GMD.1

    Give an informal argument for the formulas for the circumference of a circle, area of a circle, volume of a cylinder, pyramid, and cone. Use dissection arguments, Cavalieri’s principle, and informal limit arguments.

Geometry

  • 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.

Similarity, Right Triangles, And Trigonometry

  • HSG.SRT.4

    Prove theorems about triangles. Theorems include: a line parallel to one side of a triangle divides the other two proportionally, and conversely; the Pythagorean Theorem proved using triangle similarity.

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Teacher Reviews

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Featured review by
Samantha S. , Classroom teacher
Classroom teacher
Wilde Lake Middle School
Columbia, United States
Great resource for students and teachers-CK-12
This product is a great resource for teachers and students. This would be a great resource to use in a flipped classroom setting because of all the instructional material available as well as the practice problems available. The teacher can see what the students complete from the teacher view. Teachers can assign their students readings, instructional videos, adaptive practice, simulations and more. There is so much to offer and everything is curriculum standards based. This is a resource that is available to almost all subject areas. This is a great resource for teachers and students because it is interactive, engaging, and instructional. I recommend every teacher check out CK-12!
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