This is the BIG ONE. It gives you Structures, Wheels & Axles, Gears, Sprockets & Chains, and Pulleys & Cranks all in one. It's ideal for library makerspaces and creative spaces in classrooms. It's a giant launching pad for special challenges and school wide design/build projects and contests. Comes with 100+ free online, standards aligned lessons and activities. Includes 1224 colorful blocks, connecting, wheels, pulleys, axles, gears and chains. Storage containers and lids included.