Six spheres nest inside each other, each a different weight allowing for endless configurations. Deconstruct your tower and watch the pieces wobble. Flip the spheres upside down and build it all over again. Spin the pieces round and round, stack by size, weight or colour. The wobbling motion of each piece encourages a sense of touch while stacking the spheres high to form colourful creations will develop hand-eye coordination with the added bonus of discovering balance.