Children can build an amazing windmill generator and learn about renewable energy by using the materials provided with this unique Green Science – Windmill Generator kit and a recycled plastic bottle. Watch the LED glow as it is powered by free energy from wind. No batteries required. Each kit comes with a rotor, 1 front-housing with gear and rotor shaft installed, a back housing, 2 half-screw caps, 1 toy motor with gear (generator), 1 motor cover, 8 small screws, 1 LED with wires, and detailed instructions. Children not only can build their very own windmill generator, but also learn how to create interesting toys from daily refuse such as a plastic bottle. Lots of educational fun facts about protecting the environment can be found in the detailed instructions.