The Snap Circuits Green Energy STEM Learning Toy is an exploration in alternative energy. The STEM toy comes with more than 125 projects and over 45 parts, you'll build windmills, solar light clock, an electric car, water timer and so much more! It is a fun way to use and learn about gears, using a hand-crank for power, and a meter for watching how much power is being used. Help the environment and have fun learning about alternative power, energy conservation and how the electricity in your world works. The learning toy comes with a full-color manual and separate Think Green educational manual that explains environmentally-friendly energy including geothermal, hydrogen fuel cells, wind, solar, tidal, hydro, and many more.