Root is a small, squat hexagon, a cheerful and friendly ‘bot reminiscent of the robot vacuum-cleaning Roomba. Scanners dot its bottom, bumpers line its sides, and there’s a touch interface on top. Root knows when it’s on a magnetic surface. A little holder for a dry-erase marker sits dead center on the bot, which can draw on a whiteboard and erase it, too. Using that whiteboard, an iPad, and a language that’s super-easy to pick up, kids learn to code by teaching Root how to interact with the world.