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Are They Similar? Lesson PlanAre They Similar? Lesson Plan
Publisher
Illustrative Mathematics
Resource Details
Curator Rating
Educator Rating
Not yet Rated
Grade
9th - 11th
Subjects
Math
1 more...
Resource Types
Activities & Projects
1 more...
Audience
For Teacher Use
Duration
45 mins
Instructional Strategies
Collaborative Learning
1 more...
Technology
Calculator
Scientific Equipment
Usage Permissions
Creative Commons
BY-NC-SA: 4.0
cc
Lesson Plan

Are They Similar?

Curated and Reviewed by Lesson Planet
This Are They Similar? lesson plan also includes:
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  • Answer Key
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Learners separate things that just appear similar from those that are actually similar. A diagram of triangles is given, and then a variety of geometric characteristics changed and the similarity of the triangles analyzed. Because the drawn diagram does not change, only the labeled properties change, this activity makes for excellent stretching of those theoretical math muscles in paragraph proofs. Great for a capstone exercise on similar triangles, or end-of-course open-response practice.

67 Views 44 Downloads
CCSS: Designed

Concepts

similar triangles, ratios, transformations, parallel lines, geometric proofs

Additional Tags

math

Instructional Ideas

  • Have the class develop their own criteria that may or may not result in similarity, then justify the result
  • Link with a unit on constructions and replicating distances or angles, and add a construction portion to each similarity transformation

Classroom Considerations

  • Similarity transformations not on a coordinate plane offer a particular challenge to some learners. Allowing for drawing examples on grid paper might help those difficulties
  • Providing multiple copies of the diagram included would satisfy many needs for additional supports

Pros

  • Multiple parts force learners to evaluate each situation on its properties and not appearance
  • Careful treatment of similarity statements emphasizes the importance of vertex and side correspondence

Cons

  • Student activity not separated from teaching notes and answer key

Common Core

HSG-SRT.A.2 MP3

View 40,743 other resources for 9th - 11th Grade Math

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