Tangram day is one of my favorite days of math class. While students each individually cut their own set of tangrams, we learn vocabulary words. This is a terrific interactive way to review previously taught concepts as well as learn new terms.
One of the big concepts in 7th grade math is similarity of polygons, so I use the tangram pieces to teach congruent, similar, as well as corresponding sides and angles. Touching the pieces as we learn the terms seems to help most students grasp these before we start looking at figures on paper and trying to match up sides and angles.
The fun part really begins when students start using their pieces to create predetermined shapes. It is such a visual spatial thing that many students, boys and girls, struggle to manipulate the pieces. I love the way their minds wrap themselves around the struggle, working against themselves many times, trying to force a match where there really isn't one.
I think geometry and playing with shapes, drawing 3-D isometric drawings, etc.... are more important to the development of young minds than our curriculum allows time. Unless at a young age, students work to strengthen those parts of their thinking process, the ones that create visualization, I think it is lost forever.
For today, we will continue playing, and shaping, and stretching our brains!