This set provides four Circuit Blox 72 kits (CB-0163), all packed into a sturdy storage case for sharing in the classroom. Contains 140 parts. Requires 12 "AA" batteries. Each kit provides hours of fun and educational play. The colorful building blocks contain electronic components such as a battery module, switches, LEDs, generator and nerve tester. Each kit builds 72 different 3D circuits that teach STEM and light a heart or star, use a hand crank to generate power, or tests your nerves through a maze!