A great introduction toy to learn STEM concepts such as gravity, force and momentum, and how they can create a chain reaction.\nThis chain reaction discoveryset has a musical theme and features 52 pieces, including 3 metal and 3 wood marbles. The set helps tobuild skills like perseverance, STEM problem solving and critical thinking. Combine sets from the full range and see how big of a circuit you can create.\n2021 ASTRA Toy Award Winner- Build & Play.\n2021 Gold Winner-JUNIOR DESIGN AWARD\