Ramona the Brave is the third book in the Ramona Quimby series, focusing on Ramona Quimby's first grade year.
The book starts with the Quimby sisters going home from the park, but Beezus Quimby is angry. Ramona, on the other hand, is pleased at how "brave" she was for "defending" her older sister. When they get home, Beatrice demands that everyone stop calling her by her nickname. The parents ask what happened and the girls respond that a rude boy on the playground started chanting, "Jesus, Beezus!" and Ramona embarrassed her further by "preaching a sermon"; saying that it was wrong to take God's name in vain. Ramona now feels sad and embarrassed, because she feels that she tried and failed to be noble and brave.
Lately, Mrs. Quimby has been running errands for some reason she is keeping secret, and when Ramona can't find her red crayon and later finds it broken, the girls argue over who's at fault, which degenerates into name-calling. Ramona reads a book involving a gorilla, only for another argument to start up when she slams the book. Mrs. Quimby enters and tells the girls off for shouting, but then turns sympathetic and decides that the solution is to put the girls in separate bedrooms, which is what she plans on doing, and her secret is that she's building a new room. They can afford it as she has a new job at Dr. Perry's office. As for the question of who gets the room, they will take turns, with Ramona being first (for a change).
Howie comes over, with some bricks from a construction site, and the two six-year-olds play "Brick Factory", a game where they smash up bricks. Then, Ramona watches the room being built and is excited, but she also finds it spooky having a hole in her house.
On Ramona's first day of school, she tells the class about the hole for show and tell, but they don't believe her, and they even laugh. To make matters worse, when she shouts in embarrassment, the teacher tells her off. At the playground, Ramona tells Howie off for "lying", but it turns out that he only said no because the workmen didn't "chop" a hole like she'd said, but rather "pried" it.
In art class, Mrs. Griggs has the students make paper owls, but Susan copies Ramona's and Mrs. Griggs assumes Susan made the original and calls Ramona a tattletale when she tries to dob Susan in. Ramona destroys both owls, but then feels afraid that she "did something bad", runs away, and falls over. Mrs. Quimby, who is waiting to pick Ramona up, calls her brave for dealing with the injury well, but Ramona feels like she isn't brave.
At Parents' Night, Ramona tries to read the paper, but can't understand some of the words, substituting them mentally with "zzz". She tries going to bed early in her new room, but is scared of a woman screaming on TV, feels guilty about destroying the paper owls, and is also nervous about the gorilla from the book she read. She gets out of bed and writes a note to Mrs. Quimby saying, 'Come here'. When Mrs. Quimby complies, she is asked to reveal all she talked about with the Kemps, and when she gets to the owl, Ramona fesses up. However, Mrs. Quimby asks her to apologise, which makes Ramona feel worse. The next day, she does apologise but whispers that Susan is a copycat who stinks.
Over the next few days, Ramona has bad days and worse nights-- it rains a lot, she thinks Mrs. Griggs dislikes her, and she feels lonely at bedtime. In addition, she gets scared as a result of her loneliness and whenever she tries to talk to her family to quell her fears, they dismiss her behaviour as "stalling". One morning, the sisters talk about their nightmares, and Ramona meets Beezus's teacher Mr. Cardoza.
One day, Ramona's progress report says that she needs to "keep her hands to herself" and "work on her self control" (referring to her helping Davy with his work). This makes Ramona very indignant and she wants to rebel and shock her parents, so she tries to swear, but all she can think of is "guts", which makes them laugh. Ramona sulks on the couch and claims that her parents love Beezus more because they don't laugh at her mistakes. Beezus reveals that they used to. Ramona says that Mrs. Griggs doesn't like her and begs to be sent to Room Two, but they dig their heels in and insist she stay in Room One.
The next day, Ramona tries to change things up by taking a different route to school, but a large, angry dog arrives and she throws her lunchbox and shoe at it to distract it. At school, the teacher asks where the shoe is, and she explains about the dog. She makes a slipper and feels very brave.