If his behaviour is very different at school, it is the teacher's responsibility to find a strategy that will work with your child. You are supporting the school by ensuring a good diet. You care about his health. I would begin by making an appointment with his teacher. Say you understand he is a cause for concern. Ask what strategies they are trying to use to help your son change his behaviour. There are several standard strategies they could be using..... marbles in jar for good behaviour etc. sticker charts etc,. If he is well behaved, even shy at home... this is obviously something the school need to learn to deal with. Explain that his behaviour is very different out of school, that you will support whatever strategies they wish to employ, but as you are not with him at school, whatever you do at home will probably not help in school. The teacher needs to learn to deal with him.
