So, I made a couple of things this morning while I was supposed to be working. I had such luck with the Dodecahedron, I thought — why don’t I just do all of them? Eventually, I want to do that, but I figured I’d start with one of the easy ones, namely the Tetrahedron. You can go to Flickr and download these two images as files that will print on full 8.5″ x 11″ sheets of cardstock. Then you can cut them out, and draw sigils on the inside of them or the outside of them, or whatever. Assemble them with glue or tape, or let them teach you what you’re trying to learn about geometry. Assemble them with the white paper on the inside as a way of keeping your intentions secret, or hide something inside, with the four colored bits also hidden within, in order to charge something with the capacities of the elemental forces.
Or you can use these just for fun.
Ultimately, though, the tetrahedron is one of the effective building blocks of the universe. Take regular triangles, and stack them up in any sort of way, and sooner or later there will be a tetrahedron. It’s kind of unavoidable. The same goes for some of the other Platonic Solids — the regular polygons, and the regular polyhedrons, are part and parcel of the mathematics that describes our universe, and we’ve ignored their usefulness as teaching tools for far too long.