hi, i just wanted to say that i think what you are doing is awesome. i think its the only real way to make a difference, good for you!
dont forget that in kindergarten, most of the kids still dont have great social skills. a lot of things that can be taken for meanness are often just kids who havent yet learned how to interact. when my son first went to school and he wanted to play with someone, he would go up and scream in their face like a nut. scared them! we did some role playing (a wonderful tool, especially at this age), and he got the picture. also, just to show the other side of the coin, there was a kid in my sons class who was giving him a hard time. i talked with michael about how to stand up to him, etc etc,,,, then i was in the room for a couple of class parties, and i was watching this kid, turns out that he has a really hard time in school, is very frustrated by the work he cant do, cries a lot, etc. i felt bad for him. i took a different approach after that, told michael that he just has a hard time, he is frustrated, maybe he has a bad day and maybe he could use a friend. they havent become friends or anything, but by making the kid more human and vulnerable, the whole thing has kind of diffused.
also, i guess right now they are young for this, but their siblings arent...dont forget about cyber-bullying. it is huge.... that crowd of cheerleaders keeping the whole thing going is no longer limited to 10 or 30 kids in the playground like when we were kids, it is limitless and tremendously powerful and damaging.
best of luck to you all, i would love to hear how it goes.