hese Woodcraft Construction Kits are 3D wooden puzzle marvels for kids of all ages. Not only are they fun to put together, but they are also educational and bring out the creativity of those working on them. The units are made of 3mm plywood and the pieces are individually slotted to interlock with one another to form a 3D model. Everything is pre-cut and assembled by pushing the pieces together. There is nothing to cut or glue. The 3D Puzzles are even paintable if desired.