I have had many, many encounters with bullies in life and I too have learned the ONLY way to stop a bully IS TO STOP A BULLY. 

Last week I was at my seven year old son's baseball game and a boy on his team was getting teased by his teammates- why are you hear? you can't play baseball? go eat donkey poop...etc.  I first told my husband who was helping on the field, then I told the coach, and I know the other coach, parents and the boys heard me address this issue.  Still it continued...finally I walked over to the boys told them that (not going to say his name) is apart of their team, they need to respect and encourage each other, and that I would hear no more teasing or name-calling, and to sit down and watch the game.  Of course they acted like they did nothing wrong and that they didn't know what I was talking about...but it stopped at least for the that game.  This child was not my own, nor was my son one of the bullies-which I assure you that if it was he would have spent the rest of the game on the bench.  Sadly, the coaches did nothing to address this and many parents looked at me as if I had "no right" to say something.  I really couldn't care less, I am not going to stand by and watch a 7 year old boy be brought to tears by his own little league teammates.  I would like to add that upon discussion with my own children the next morning, my son said he wouldn't say things like that because last year he didn't hit the ball at all and he wouldn't want his teammates to be mean to him.  Respect and sportsmanship should be a major part of team sports for little kids-please parents/coaches if you see it; act-don't ignore and say it will work itself out.