OK, I saw a part of the movie on TV but I think the title was wrong and I can't find it no.
In this movie, a kid with long blond hair has some psychopath thoughts, he killed a classmate because he made fun of him, he was wearing a mask when killing him. In the meantime his mother was called to the school because they were noticing that weird behavior. I think the movie was film in late 70's or early 80's
Thaks
