Ask for a meeting with his head teacher and the head of the school. Say that you understand these things occasionally happen, but you have seen no evidence that the problem is resolving and you are not reassured. The school should have a plan and they should have a way of coping. My oldest was a day care baby, and she was bit several tiems by one child. I found out WHO by accident, but they did tell me the circumstances in that one child targeted my daughter more than others, although she also bit other kids. It was becasue they were friends and always next to each other (at lunch, lining up to go outside, etc.). When this one child felt he needed attention, my daughter was an easy target. They had no problem explining that to me without telling me the child's name or even gender. I think you are entitled to know the CIRCUMSTANCES so that you can work with your child and can work with the school to address it.
I have attached below a response I sent to another mom who was the parent of the biter. Basically, many kids do try this, and I think it's normal, but that doesn't mean it can't be resolved. TO be honest, it is one of several reasons I left day care - It was difficult to see my child hurt and no I had no power in the situation.
Your child should not be continuoously assaulted. And if he is, then the school needs to move the aggressor or dismiss him/her. That was our school's policy. It took a couple of weeks, but the issue with my child resolved and the biting stopped So I say, give it time, but don't ignore it either. They need to prove to you tha they are being respnsive. Additionally, take this as a learnign opportunity to teach your shilcd to say no to innappopriate touching. I would point at my daughter's bruise and tell her "No one sould hurt you" and "It's your body" and "Say NO-NO!"
Older response: Work with the daycare provider to come up with a consistent action plan. My daughter was on the receiving end of this a few times - and no, I didn't feel real happy wiht the other family, even though I know this is a stage for some kids :) And you would feel the same way if you son came home with black and blue teethmarks, wich he may sometime in his daycare career. Here is what my daughter's day care did.
They "assigned" a teacher or aide to be with "the biter" or watch him during times where there was likely to be stress or frustration and the biting occurred. This was usually getting the kids ready for naps or lining up for the playground.
When he bit, they said in no uncertain terms "No biting!" No extra words or discussion. No yelling. Just calmness and quick reaction. He was quickly and unceremoniously removed to the side of the class to sit quietly with no playing. It helped that my dughter learned to say, with my instruction, "NO! HURTS!"
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