Electric Plane Launcher

This kit’s great for office warfare but it’s really meant for flight-testing paper airplanes. Two DC motors spin rubber discs in opposite directions to grab your plane and propel it up to 30mph. There’s no soldering, just pre-cut wires and a screw terminal block.

Intended for teaching kids ages 14 and up, it’s easily assembled in minutes with a screwdriver (included); you add only batteries. I’d say kids 10 and up could build it, with adult help to push the motors tightly into grommets. Caveats: the instructions have some inconsistent drawings (the online video helps), and the front leg is fastened by a nut on the deck directly in the plane’s path — a dubious placement, though it hasn’t tripped up my planes yet. (Incoming, Jake!)