  YAY!!! Big post!!! Anyway, answer to question: Because it has worked before. Like Coach Hart says, if the behavior has been rewarded before, it will most likely happen again. Meaning, of course, that every time he goes crying to your mother and she makes you get off so he can get on, she is rewarding the crying, stomping, biting?!? that comes with it. Answer to poll: I never bit anyone in kindergarten, but I did kick a boy in first grade. I like the unplugging the monitor idea- Julian does that to me all the time. It's very annoying and very effective. 
