I have to agree with the original poster, and other respondents.. it is very different to refer to someone as being a "rude boy" as opposed to saying that it is rude to interrupt. It is not at all "splitting hairs".. it is a negative comment on an entire person vs. a negative comment on a particular behavior choice. I also don't think it is a blip on his radar. Her son was upset enough to come home and tell his mother, even though it involved admitting that he was speaking out of turn. He was clearly very upset by this and it will stick with him. I also agree with the OP that it shows frustration on the teacher's part... not very professional to blurt out a comment like that, especially in front of the whole class. Perhaps it was a bad day, or perhaps she is specifically frustrated with this child. Either way, any teacher should know that you do not insult the child, you identify the problematic behavior. I would speak with the teacher and find out if she is feeling frustrated with the child, and why. I'd explain that, although he knows his behavior was wrong and he will work on not speaking out of turn, he was upset by her comments.