Fun interactive application to form structures with unit cubes

From the virtual manipulable collection for the teaching-learning of basic mathematics, the work of the Specialist in mathematics and Laureate Juan Garcia Moreno, almost certainly, it is the free, Flash collection, the most extensive, varied and interactive that can be find on the net.
This series of activities consists of the formation of polycubic structures and sculptures from unit cubes, semi-cubes, bars and plates that are presented in two different perspectives (isometric and knight). You can get as many copies of each unit polyhedron as you like. Several different screens or scenes.