Website
National Council of Teachers of Mathematics

The Math Forum: Making Patterns

For Teachers Pre-K - 1st Standards
Explore the literature connections, online activity, pencil and paper activity, and the manipulative investigation of patterns and geometric shapes on this page!
Website
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.
Website
Science U

Science U: Welcome to the Geometry Center!

For Students 3rd - 8th
Site provides information and activities on various aspects of geometry, from shapes to patters and symmetry. Make your own tetra puzzle or build an icosahedron in the classroom. Interactive and fun.