If a kid being bullied/harassed doesn't speak up and it doesn't happen right in front of the teacher, how is the teacher supposed to know what's happening? Kids lose interest and get depressed all the time, it could be bullying, they could be having problems at home. Teachers are not therapists. They are not trained to recognize warning signs of anything. That's why schools have guidance counselors and principals for kids to talk to. Yes, there could be some preemptive measures taken at the beginning of the class but that often gives the little bastards doing the bullying more ideas. If the OP had been more involved (not just interested in bragging about, but really involved) in her child's life and recognized the warnings signs (that she easily picked up on months later) then she could have done her job as a parent an intervened. It's your job as a parent to watch out for your children. You should know them better than anyone. If you didn't see the signs, how could a teacher who barely knows your child pick up on them?