Dumb Like Me, Olivia Potts — Lila Perl

Olivia's sister Meredith was editor of the high school literary magazine, her brother Greg had just started at Yale on a scholarship, and her mother was enrolled at the local community college. But Olivia didn't even like school. “You're just going to have to learn,” she hissed in an imaginary conversation with her fifth-grade teacher, “that some of us are dumb. Dumb like me, Olivia Potts.”

Then Olivia made friends with a new girl, Anita Brunelli, who didn't seem all that brainy either, but who was good at figures. It was Anita who helped Olivia see the connection between her father's stolen license plates and the strange things Olivia had seen going on one afternoon in the backyard next door. But it was Olivia herself who discovered, in the scariest possible way, who was behind the thefts in the neighborhood.

And Olivia, the detective, discovers that perhaps she isn't as stupid as she thought she was.