I completely disagree with the suggestion to help build the self esteem of the bully, as was suggested, by getting them a babysitting job. You’re going to put a bully in charge of other children? The best way to show compassion to a bully is by not allowing them to get away with it.
I think a lot of institutions profess to have a zero tolerance policy towards bullying, but fail to follow through with action. They treat physical altercations differently than verbal ones. A physical fight results in a sure fire phone call to parents and possibly stronger interventions, such as suspension from school/camp or the bus, time outs, etc.
Kids who verbally abuse others MAY be spoken to, at most. Their parents are not called nor are they suspended from school/camp or the bus. Why would they be motivated to stop?
I know this as fact as I have kids who have been on both sides; perpetrator and victim.