Day 10: Paper plate icosahedra

We needed some decorations for the school dance tomorrow night. Laurie D found a picture of an icosahedron made from paper plates and wanted a few of them to be hung from the ceiling. So I made some. At first I did some trig calculating how long each side of the isosceles triangles would be, and then realized that I could just count the ruffles around the edge! Then fold, and staple. These would be really cool to make out of interlocking pieces of plastic, and then lit from inside.

They are quite stable once they are all put together (they are geodesics after all).