Over the course of the book’s events, Scout matures by learning empathy. This is something she struggles with at the end of the book.
When Scout has problems with her teacher Miss Caroline, Atticus tells her she needs to learn empathy.
"[If] you can learn a simple trick, Scout, you'll get along a lot better with all kinds of folks. You never really understand a person until you consider things from his point of view…until you climb into his skin and walk around in it." (ch 3)
At that point, Scout is having a lot of trouble looking at the world from another person’s point of view. Yet as she matures, she begins to get the hang of it. One example is during the trial. Despite Mayella being on the other side, Scout is able to empathize with her.
As Tom Robinson gave his testimony, it came to me that Mayella Ewell must have been the loneliest person in the world. (ch 19)
Scout is able to hear about Mayella’s life and feel sorry for her. She can put herself in her place. She does the same thing with Boo Radley when she stands on his porch at the end of the book. She has learned empathy. Scout is becoming more mature.