Cube, Octahedron, Icosahedron
A modular origami which lets you make a cube, an octahedron, an icosahedron and so on, by Stephan T. Lavavej.
The module used is a variant of the sonobe module, it’s really easy to make, but the icosahedron is a bit tricky to assemble. I used 10cm square paper and it’s quite sturdy.
Paper to use
You need 6 modules for a cube, 12 for the octahedron and 30 for the icosahedron. I used 10cm wide square papers to make the modules.