What you said
It sounds as though the school needs to do what one institution in Wales did recently - a new head arrived and operated zero tolerance. Parents and pupils were told in advance that pupils would be sent home if they arrived in non-regulation clothing, were abusive and so on. They apparently sent 200 pupils home on the first day but stuck to their guns and had a marked improvement in educational outcomes that year. Log all infringements and make sure any physical assaults are officially recorded.
The expert view
You sound as if you are suffering from one of the hardest things to solve: a school that is weak on behaviour.
1. Find others who have good behaviour in their lessons. Talk to them, observe them, get them to observe you and offer advice.
2. What are the school sanction options? Use as many as you can. You can set detentions, surely? If the pupils fail to attend, then escalate into more serious sanctions. If it gets worse, press for exclusions.
3. Phone calls home are only effective if the parents buy into what you are saying, so try to be positive but disappointed rather than angry with parents. Ask them to help you by supporting a detention or administering sanctions at home.
But little of this will help without supportive line management. You need backup. If a school does not support its teachers in behaviour management, it does not deserve to have any staff or children. If it is that bad, look somewhere else. There are better schools out there.
Tom Bennett's latest book, Teacher, is out now. Post your questions at www.tes.co.ukbehaviour.