Pi in the Sky — Wendy Mass

Joss is the seventh son of the Supreme Overlord of the Universe, and all he gets to do is deliver pies. That's right: pies. Of course these pies actually hold the secrets of the universe between their buttery crusts, but they're still pies.

Joss comes from a family of overachievers, and is happy to let his older brothers shine. But when Earth suddenly disappears, Joss is tasked with the not-so-simple job of bringing it back. With the help of an outspoken girl from Earth named Annika, Joss embarks on the adventure of a lifetime and learns that the universe is an even stranger place than he'd imagined.