Build Your Own Polyhedra Author:Peter Hilton You need to build it to believe it! Sharpen spatial skills by constructing a myriad of configurations from regular polygons, flexagons, regular and pop-up polyhedra to dipyramids, Jennifer's puzzle, dodecahedra, and collapsoids. This book includes illustrated instructions to create various 3-D shapes; it also delves into Euler's formula and how ... more »to braid Platonic solids and rotating rings. Grades 6-12« less