When Kitten mistakes the full moon for a bowl of milk, she ends up tired, wet, and hungry trying to reach it.

"Willow is shy. VERY shy. Her home is in an abandoned mailbox, and she'd rather stay put. Outside kids scream and soccer balls collide, trees look like monsters, and rain is noisy in a scary kind of way. It's much nicer to stay inside, drawing. But then a young boy drops a letter in Willow's mailbox: it's a note to the moon asking for a special favor. Willow knows that if she doesn't brave the world outside, the letter will never be delivered, and...

When seventh-grader Piper's father is hired by Chumley Prep, a school where every student seems to be the best at everything, she gets the chance to compete for the prestigious Excelsior Award.