Tinker (RoboTales, book 1)

"Recycle and create." That's Tinker's motto. He's an inventor, who lives with his uncle and cousins on planet Kitz. The Invention Institute is having a Recycle Race to choose a new apprentice for their boarding school for young inventors. Tinker builds an airbike for the contest. When Tinker's cruel cousins destroy it, a robot dog helps Tinker fix his entry in time to compete.