My email to the new teacher got a very good response. She will assign him a very nice child as a buddy and rearrange seating so he is at a table of very kind and gentle children. She also wanted me to tell him in no uncertain terms to tell her if he heard more remarks like that. He was worried about "tattling" and thus said nothing--probably socially savvy, but later it ate at him. She said he did beautifully with the work.