Icosahedron at vismath
Using this ITSPHUN-kit one can build all five platonic solids: Icosahedron, Dodecahedron, Octahedron, Cube and Tetrahedron. The pieces can also be used to make up any other forms you like!
The ITSPHUN polygons can easily be transformed into different 3D polyhedra. The faces are made from ecofriendly PP-material and they can be connected using the notches on every edge.
Zometool: Creator 1
This is the kit to get started with Zometool. The colored instructions explain the structural properties of different geometries. With this kit you can experience a multitude of geometrical solids and their relations on different levels of difficulty. Show your kids with this construction kit how manifold and exciting geometry can be.