Building upon the multi-faceted early childhood development benefits of unit block play, each solid beech truck in The Block Science Big Truck series is designed to overlay a lesson on how a simple machine works. This large wooden cement truck carries a cement mixer which is connected to the wheels of the truck by 5 different gears. When the truck is moved, the cement mixer turns, teaching children to recognize and investigate the mechanics of using gears. Unit Blocks and these accompanying Block Science; Big Trucks teach simple machine and STEM concepts while encouraging construction, deconstruction, teamwork, social interaction and self-expression. Dimensions: 15.25"H x 5.5"D x 9"L. Suggested Age: 3+