I work in a large secondary school, teaching a compulsory core subject.
I've just taken on a GCSE class who, on the whole, don't care about learning and are in very bad habits. According to the TA in the class, this is partly as a result of being given to a cover supervisor for the last two terms of last year who apparently let them get away with whatever they liked and expected very little work.
In the first week (alongside literally every child causing a problem like refusing to sit in my seating plan, calling out, answering back, challenging my authority, wasting time, arriving late, arriving with no equipment or their book, using a mobile phone without permission, failing to complete homework etc.) and doing my best to teach lessons they wanted to be part of and learned something from, I had to break up a fight between two boys, had to confiscate a device on which a boy was taking photos of me, had to back away from a boy who tried to stand over me and put his arms around me for intimidation, and deal with another who deliberately and repeats things I say, substituting insulting or vulgar terms.
The boys who hit each other were removed by SMT. The only thing I can do is keep the others in detention with me at the end of each lesson, where they have continued to defend themselves, be rude and back each other up, wasting my lunchtime and forcing me to spend nearly three hours in total in their company at a time. My Head of Department is aware, as are the parents, but they don't seem to care.
AIBU to think there are just no consequences for poor behaviour and I can't make a difference to any of this on my own?