Set up a meeting with your son's teacher to discuss his behaviors. It's great that he is getting his work done at home, which shows that he is able to control his behavior.
When you meet with the school, share what you do at home that helps him get his work done. It might be helpful if a resource teacher came to work with your son, or if his teacher took him to a different room during in-class work time so the distractions are removed. This might also be a good time to come up with alternative ideas, such as a reward system for when he does well and gets his work done.
