Spinerama

Spinerama is intended for children 3 and up.
The toy is wound up, and each of the wheels on the bottom spins in the same direction. The Spinerama accelerates until it reaches a point where top flaps hinged to the toy, open up.
This toy teaches kids about potential energy from a spring to kinetic energy. It also teaches kids about inertia and centripetal force.
The toy will be made out of plastic so it is durable as long as it is not subjected to extreme forces. The wheels may be choking hazards for small children, but the toy is safe to play with overall.