Party! — Diana G. Gallagher

Claudia is tired of being left out of popular princess Anna's parties, so she decides to throw one of her own. The problem is, parties are expensive. To foot the bill, Claudia takes on extra jobs. But between school, babysitting, dogwalking, and running errands, she doesn't have much time left for her friends. What good is a party when there's no one to invite?