Role playing exercises for bullying can serve two purposes: building empathy and teaching skills. Which purpose is most appropriate for any given child will depend on her specific situation, as will which kind of situation will best serve a given purpose. Though the variety of potential situations is literally infinite, most fall into a few broad categories.
This is a simple empathy-building exercise in which a bullied child plays the role of the bully, and vice-versa. For the child who usually bullies, it can help him understand how his actions affect his victims. For a child who is often bullied, the role reversal should include some speculation about why the bully does what he does. This can help the child identify ways to communicate with a bully in a non-confrontational way.
Not all bullies are open to empathy and communication. Bullyproofing role plays teach children to deal with that kind of bully. In this situation, an adult or trusted older child plays the role of the bully. The bullied child practices avoidance and escape skills in the context of the game. This kind of repeated practice can help the child understand how to avoid being bullied, and to apply those skills under the pressure of a real situation.
Bullying usually happens in public, because bullies do what they do for the attention and praise their behavior elicits. In a stepping up role play, participants play the role of the bystanders in a bullying situation. They practice de-escalating the confrontation, coming to the aid of the bullied child, or simply refusing to give positive feedback for the bully's behavior. Children who practice this skill may then be ready to do the same in an actual bullying situation.
In a school environment, bullies can get away with bullying because schools require specific documentation of bad behavior before they can punish a child. Because children aren't noted for their excellent, objective recall of details, a role playing exercise where they play the role of a bullied child, then remember and report what happened, can be useful to both the child and the adults responsible for his safety. In this kind of role play situation, an adult should always play the role of the bully to keep feelings and even physical behavior from getting out of hand.