Amber and her best friend Justin are spending the summer at Camp Cushetunk. Amber is having a great time learning to ride and take care of the Cinnamon, the sweetest horse ever—until she becomes the target of pranks. Amber and her friends plot revenge, but things don't turn out as planned and the horsing around leads to real trouble.

Aliens have finally made contact with Earth and have sent an ambassador-a single parent who brings along his kid, Pleskit. Because his father insists he mix with earthlings and attend public school, Pleskit becomes the world's first sixth grade alien. His initial attempts to fit in are hilariously catastrophic, and only when he establishes a tentative friendship with Tim Tompkins does Pleskit begin to understand that he is being sabotaged. But