It's a toss up between Cinderella and the Br'er Rabbit books (Enid Blyton).
Funnily enough, in grade school I devoured literary fare (Little Women, Shakespeare, etc) and encyclopedias (favorite subject matter being dinosaurs, Greek and Roman mythology, and the solar system/stars/universe). If I was bored enough, I'd even read the dictionary. Nowadays, my reading material appears to be limited to trashy romance novels.
