Tridio A new concept to enhance children‘s three-dimensional perception. Children learn to represent three-dimensional objects on a flat surface. They first make a construction using cubes, then they learn to recognise the different sides of the cubes as separate shapes, each with their own colours, after which they „form“ the cubes using puzzle pieces on a flat surface. The illusion of depth and perspective occurs on the flat surface. Suitable for all ages. Contents (x10): 2 game boards 9 3-D cubes 12 triangles 27 rhombi 27 exercises 3 correction sheets 1 manual