Non-violence
The novel's main theme is non-violence, because it is the story of a non-violent child coming to age in a culture he considers to be violent. By asking children to help kill birds, he fears that his community is becoming increasingly aggressive and violent. But more importantly, he fears for his own self. He doesn't want the emotional guilt of violence on his hands, but everyone he knows is telling him that killing birds is morally correct. He must defend his non-violent views as a ten-year-old in a sea of people who already have their minds made up.
Peer pressure
The bullies taunt Palmer when they don't like his opinion, and they often make him feel scared or embarrassed when he fails to fit in with them. They pressure him into becoming more like they are, and they represent the pressure that he feels to participate in his culture's shared violence. He feels that by succumbing to their ideas, he will become violent. In the end, he sees through the peer pressure and figures out a way to do the right thing.
Malice and meanness
When someone intentionally tries to harm someone else or their life, that is called malice. This book shows thematically that the pigeon hunt (as Palmer experiences it), and the bullying are related. The boys are mean and malicious, and Palmer believes that they are this way because they are influenced by their surroundings. He feels that by hanging out with people who are mean, he becomes mean toward Dorothy, so that invites the reader to suspect that the bullies are mean because they too have learned behaviors from their broader culture.
