Burned an hour this evening exploring www.lessonplanet.com . Our school has a month-long free trial. I compared the results from this site to a regular Google search. The results were very similar. Lesson Planet has some original plans and many links to public plans. The four plans I liked best are available free online. With that said...
This week, I am taking a really close look at the second-grade common core standards for Geometry. Envision, while wonderful, great, etc., lacks extended practice & rigor with polygons & their attributes that standard 2.G.1 requires.
I have found some great lesson plans. Several of them center around a really cute book, "The Greedy Triangle."
Here are links to lesson plans that I am 'beefing up" to fit the TEAM model and common core.
The Greedy Triangle - Exploring Polygons with Geo-boards
The Greedy Triangle Lesson Plan (graph paper)
Polygon Scavenger Hunt
This plan includes a great foldable, Exploring Polygons with the Greedy Triangle .