Behaviour was a huge problem at my school all the way through to Year 11. I was in all the top sets, but in my year group the most disruptive people were also some of the most intelligent (despite the fact they never did any work) so I arguably had a worse time than those in the lower sets. It wasn't just constant, never-ending chatter, either - I had classes where people would throw things at the teachers, scream at them and throw huge toddler tantrums when they were told to be quiet, swear in their faces and call them disgusting names etc. These were never just one off incidents either, they happened consistently every lesson for years. I remember Year 9 & 10 Maths being particularly awful, as we had a very sweet, shy, female Indian teacher who was an excellent teacher when allowed to teach, but she was viciously bullied by the people in my class for two years and it was just horrendous to watch. Asides from the fact that I learnt very little, what horrified me the most was that these girls could be so incredibly cruel to somebody and not bat an eyelid, and they weren't even the thugs that every school has - they were intelligent, high-achieving pupils. Nothing was ever done about any of it; occasionally the senior teachers would make a big show of removing the odd disruptive student from a lesson, but they'd always be back the next day and the cycle continued. I think the reason they never took it seriously was because nobody would ever really believe the select few of us who actually wanted to work when we told them what was going on - it was the sort of behaviour you might expect in a bottom set full of people who didn't want to be there, but it wasn't something they wanted to accept was going on amongst the highest achieving students in the school.