Lightsabers! Use the Force and become a Jedi .... or a Sith!
You can now build your own! Kits available at the Parts and Crafts Store!
This project comes from Parts and Crafts, developed from 2008 - 2011. Parts and Crafts is a creative community & summer camp for children to learn in an environment in which they are freely able to choose what they are doing. Parts and Crafts grew out of a camp I started in 2006 called Camp Kaleidoscope, which I directed through 2008.
The lightsaber kit was conceived of at Camp Kaleidoscope in 2008, and has since gone through several revisions by Parts and Crafts. We've tried it out in several public workshops, where children as young as 6 or 7, as well as parents and adults, have tried and generally loved the project. The project serves as both a reasonable introduction to electronics -- as it requires no prior knowledge -- as well as a fun way to explore making electronic props for costumes (especially for Halloween!)
And for those interested, here's a blog post from 2008 when I was running Camp Kaleidoscope, telling a few stories I saw around kids making lightsabers and what I saw them learning in the process.