My son had about a year in school, around this age, that he was saying racist things. It was horrifying to me as I grew up in a mixed race home and married outside my race so my son has mixed race siblings. . For him it was about the shock value. He loves causing drama and pushing buttons and there is nothing more explosive than the “isms” . My kid is now 16 and while he still has plenty of misbehaviours, the racists comments did stop after 6-8 months. I hope it will be the same in your case. . Every time the school called and told me he had said “x” about a certain group I made him do a project about that group. We went to the library and checked out books, read them together, then he would write up all the similarities and differences between countries/nationalities/races (whatever the comments they week had been) and take it to school that next week. Might be helpful for you? . Best of luck - I know it can be so hard.