You’ve heard this theory before: The classroom bully acts aggressively toward others as a way to compensate for the fact that, deep down, he really doesn’t like himself. This may be a satisfying explanation for bad behavior, but numerous studies show it to be untrue. Indeed, research shows bullies feel just fine about themselves; some studies suggest that they have excess self esteem and feel better than others. (Some researchers speculate that this is one of the ways they rationalize their behavior.) This doesn’t always mean that bullies lead a blithely carefree life, however. The Centers for Disease Control has found that bullies are more likely than other students to experience violence at home.

Taylor Weidman/The Christian Science Monitor
A group of students from Oliver H. Perry K-8 School in South Boston, Mass., perform a skit about bullying at the Vine Street Community Center. [Editor's note: An earlier version of this caption misstated the Boston neighborhood in which the Perry school is located.]