Oh poor you. Make sure that his teacher and school know about the problems he is having at home - death in family, house move, and parents splitting up - these are all major things going on for any child to cope with.
Is there help within school, lots of school will have specially training staff to help with emotional problems within school. (Infant schools have nuture rooms), senior school with have councelling sessions if needed. See the head teacher, explain the problems your lad is going through and ask what help is available in school. Excluding him is only adding more problems. Make sure the school know what he is going through.
Try to get him to talk to you, about how he is feeling. The more you talk the better things will be, he is probably bottling it all up inside.