With Ravensburger GraviTrax The Game Flow, you experience an interactive marble run system as a gripping puzzle game. The set includes 30 diverse challenge cards in various difficulty levels that test your logical thinking. By combining transparent levels, FlexTubes, and swirls, you build and experiment playfully with the laws of gravity. The modular system allows for custom designs and can be expanded flexibly. This game promotes STEM understanding—science, technology, engineering, and mathematics—directly through building.