The listing, Electric Pencil Sharpener Ages 14+ has ended.
Sharpen some pencils — and your engineering knowhow — with a pencil sharpener you built yourself! Follow step-by-step instructions to construct the core, add the battery, and wire your mechanism up. Then learn about the invention of pencils, the evolution of sharpener design, and cool engineering features in your sharpener (like the limit switch, which lets the electric circuit know when your pencil is in the sharpener, causing it to automatically switch on)!