With Mr. Quimby going to college and Mrs. Quimby going to work, it's a good thing Ramona is big enough to ride the bus to her new school all by herself. Unfortunately, after school she has to stay with Grandmother Kemp until her moody big sister Beezus comes to pick her up.
It's a good thing Ramona is so mature these days: she is doing her best to help Beezus make dinner and to be nice to pesky little Willa Jean after school. She can't help it if Danny — better known as Yard Ape — insists on making her school life difficult. Soon Ramona is living up to her reputation, accidentally squashing a raw egg into her hair at the cafeteria and throwing up in her classroom. Will life ever get any easier?