Winner of the Dr. Toy Best Children's Vacation Products award, this is the building block set that allows children to construct limitless geometric structures while promoting the development of spatial reasoning skills. The durable plastic octahedral shapes nest together, so there are no "wrong" combinations. The 125-piece set facilitates creative exploration while at the same time provides fundamental instruction using a full-color instruction booklet that gives tips and techniques for creating futuristic vehicles, edifices, or creatures. The set includes 36 phosphorescent pieces that can be integrated into any design to highlight key design features when the lights are turned off. Ages 3 and up. 17" L x 11" W x 14" D. (12 lbs.)