What valuable lesson did Scout learn in To Kill A Mockingbird?

Scout learns many lessons in To Kill a Mockingbird. She learns that sometimes the rules don't apply to everybody, as is the case with the Ewells. The children in the Ewell family do not attend school, and Mr. Ewell hunts out of season. Scout also learns that life is not always fair. This lesson is learned as she sees an innocent man convicted of a crime he did not commit. Through Tom Robinson's ordeal, Scout learns that people are often judged based on the color of their skin. However, perhaps the most valuable lesson Scout learns stems from her father's words in chapter 3.
Atticus tells Scout, "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." In the beginning of To Kill a Mockingbird, Scout is terrified of Boo Radley. She believes the stories about him, and is almost ill when she learns that Boo covered her with a blanket on the night Miss Maudie's house burned. Gradually, Scout's perception begins to change, and by the end of the story, she feels much differently about Boo. Boo saves the children's lives, and Scout is able to understand why the sheriff doesn't want to involve Boo in any way. When Scout says that to involve Boo would be "sort of like shootin' a mockingbird," she shows that she has learned compassion.