My school claimed to have a tough anti bullying policy and have zero tolerance etc, but in reality they did nothing, i was bullied in year 7 which my head of year attempted to sort out and nothing really changed, eventually the girl got bored and moved onto someone else by the end of year 7.
In year 10 and 11 i was having loads of trouble with someone i used to be friends with, and when reporting it to my new head of year they turned around to me and said well your not friends anymore what did you expect? (not a good thing to say to me when i was already in tears), she was really rude, and she didn't even attempt to talk to my ex friend. My parents then got involved and took the matter to the head who also did nothing.
One friend I had reported a group of guys who bullied him repeatedly (because no one did anything about it) just for a teacher to turn around and have a go at him for constantly reporting the bullies as it was harrassment etc and wouldnt believe that he was being bullied.
No one took bullying seriously at my school which led to a lot of bullying happening as they knew they could get away with it, I think schools like to pretend they have zero tolerance policies etc to look good on paper, but in reality either it doesn't exist or they don't actually stick to it.