That is just sickening. Sounds like a truly incompetent teacher to me. I realize there are some kids who are more difficult than others, but this one apparently has identified problems. Seems as tho if the teacher couldn't handle him in her class, she should have taken that up with her principal.
It's terrible to let kids think it's okay to do that to another kid, and it's even worse what it apparently has done to this little one.