Although the book is ostensibly about Ramona, a rambunctious and self-possessed eight year old, it is really about the entire Quimby family. The story's main theme is the importance of family and this is never more obvious than at the very end when a complete stranger in a restaurant pays for the family's meal because they remind him of his own family. From this we can see how lucky the Quimby's are to have each other all the time; the man is not so lucky and he misses his family, particularly his grandchildren. This is a particularly poignant moral to the story given that for much of the book, the Quimby's have been a little testy with each other.
It's a stressful time for Ramona's family and the book neatly portrays how things such as money worries, and growing pains, can affect the entire family. For example, when Beezus is in a bad mood, the entire household seems to take on a grumpy demeanor too. Even the inanimate objects in the home seem to be willing accomplices to this as the log in the fireplace refuses to burn and dinner doesn't seem to taste very nice. It's easy to see how feeling negative about one thing leads to a general air of negativity that permeates everyone and everything around it.
One of the main purposes of this book is to show the importance of a positive outlook. There are many examples of this; Ramona has a very positive outlook about her new school. She has a positive outlook about a boy she believes at first will be her enemy - although she has nicknamed him Yard Ape the two end up friends, and this is a lesson to readers about not judging on first impressions, because often thy are wrong. Ramona also finds a way to remain positive about her time being watched after school; she uses her new task of silent reading to avoid further babysitting duties of her own. The book tells readers that whatever the obstacle, there is always a way around it.
Despite Ramona's outward appearance of confidence, she is extremely upset when she thinks that her teacher doesn't like her. Let's face it; she is eight years old, and there are times when she is a nuisance, just like every other eight year old on the planet, but she learns that finding her to be a bit of a pest doesn't mean that her teacher doesn't like her. A person can find someone annoying, or a bit of a pest, but it doesn't mean that they dislike them. The book also shows readers that a person has many facets to them; Ramona is indeed annoying and loud sometimes, but she is also smart, enthusiastic and funny. Nobody is just one thing, and everyone has something about them that is likable.
This is a book that on the surface seems like a fun and jolly story, but in fact the narrative is filled with important lessons about family, kindness and the power of positive thinking.