I used them for this project featured in popular science magazine a couple years ago. https://www.popsci.com/node/1607 My kids love it.
Select as Best AnswerUndo Best Answer
if you want to generate power you could just keep the gears and motor assembly from the disc tray together and connect it to the thing you want to generate it with such as:
a bike wheel
a hand crank
a model wind turbine
or to any other thing you can think of.
hope this helped!!!