Aimed at kids 8 and up, this kit has real heart. Its 48-page workbook and components (solar cell, buzzer, two motors, LED, capacitor, copper rivets, pinwheel, etc.) take you through lessons and fun experiments that teach the basics: What is energy, as distinct from force? What forms does it take? How can it be converted between forms?
My daughter and I had fun making the solar-powered fan, electric car, and other projects. She’s a bit young for the kit, so as she used various bits to decorate a finish line for the solar car, I experimented with what else I could power, and for how long, with the 6-farad supercapacitor — those things are amazing. One recommendation: add your own alligator clips (without the leads) to make the solder-less joints less tweaky.