Brain Builder Set -2 Convert 2D diagrams into 3D structures. Train young brains to think in multiple dimension with this interactive STEM tool. Brain Builder combines 20 wooden planks with a set of stimulating puzzle cards. Perfect for even the youngest of builders-each card features a fun, recognizable 2-D object and the goal is to recreate the pattern into a 3D structure . From picnic table and bridges to dragonflies and triangles ,you will be amazed what your brain will build.