"They'd never suspect the secret I was hiding"

If you're looking for a good book for the beach, try Summer of the Gypsy Moths by Sara Pennypacker. After her mom leaves her (again), Stella is sent to live with her Great Aunt Louise, who tends to a cottage colony on a beach in Cape Cod.  Foster child Angela is living there, too, and even though she and Stella are about the same age, they do NOT get along.  When Louise suddenly dies, the girls are afraid they'll be thrown back into the foster care world; they secretly bury Louise and decide to team up and manage the cottages, surviving on the vacationers' left-over food and tips.  The story is told in Stella's voice, and her descriptions - from families tumbling out of their cars to begin vacation to her on-again, off-again friendship with Angela  - are spot on.  But how long can the girls keep their secret?