Teacher's Workshop

George Hart

Here's a large cardboard construction I made with a group of teachers from Math for America.  It consists of sixty identical flat pieces that lock together with slots. The design is based on the twenty face planes of a regular icosahedron, so the result has 5-fold, 3-fold, and 2-fold axes of symmetry.

I pre-cut the parts on a band-saw and brought them with me.  Assembling them took over an hour and was trickier than I expected, but I learned a lot about how to organize it next time.

The completed star is quite rigid and for a while we suspended it from one point, so a three-fold axis is vertical. It looked good hanging like that, until a surprising thing happened...

To understand the design first see the "Blue Paper Model" video,
then watch the "Teacher's Workshop" assembly video, both here.

Thank you everyone who participated, with special thanks to Noah Heller for inviting me and taking these photos.