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Other

Tessellation World of Makoto Nakamura

For Students 9th - 10th
There's more to do here than just look at Escher-like tessellations. You can watch animated tessellations and put together puzzles.
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Primary Resources

Primary Resources: Patterns and Symmetry

For Teachers Pre-K - 1st Standards
Teachers, here's a great resource for worksheets and presentations about symmetry. Includes PowerPoint and smartboard presentations.
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PBS

Pbs Learning Media: Triangles

For Students 3rd - 5th Standards
In this video segment [2:01] from Cyberchase, the CyberSquad finds that by arranging triangle tiles they are able to create a path that will allow them to cross a river of hot lava.
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PBS

Pbs Learning Media: Squares

For Students 3rd - 5th Standards
The CyberSquad builds a raft out of squares in order to cross a river in this Cyberchase video [2:05] segment.