How do Scout, Jem, and Atticus change throughout To Kill a Mockingbird?
All of the characters change to some extent during the course of the novel as they are affected by events in different ways. Nothing in Atticus' solid principles or sense of morality changes, but Bob Ewell's despicable attack on Jem and Scout shakes Atticus and makes him aware that there is a greater potential for evil in human behavior than he had realized. It had occurred to Atticus that Ewell might come after him, but it was beyond his imagination that Ewell would attempt to kill his children.
Jem and Scout grow up in significant ways. Jem goes through puberty, becomes moody for a while, and seems to move away from his little sister, which upsets and confuses her. The greatest change in Jem, however, is that the terrible injustice of Tom's conviction disillusions him and makes him question his neighbors' goodness and human nature itself. He turns to his father to help him understand that which he does not understand.
The greatest change in Scout is seen through her relationship with Boo Radley. From the little girl who played "Boo games" with Jem and Dill, she becomes the sensitive and enlightened older girl who holds Boo's hand gently and walks him home. Standing on the Radley porch at the end of the novel, Scout sees the neighborhood, literally, from Boo's point of view and remembers the child she used to be.