What is the problem and the resolution?

The main problem or conflict is a misunderstanding between Ramona and her teacher, Mrs. Whaley. After an incident in which Ramona breaks an egg on her head (copied from anoher student Ramona wants to be friends with), her teacher labels her a nuisance.... a show-off. Unfortunately, Ramona translates this to mean her teacher doesn't like her.

The problem isn't resolved for a long time. Ramona initially shuts down.... her feelings are hurt, she gets quiet, and she isolates herself. The resolution finally occurs when Ramona actually talks to Mrs. Whaley about what she heard.