How are things going? Hopefully, you'll still be in the honeymoon period where pupils listen to you and do as you ask. If they're not all behaving well, tackle it before the chaos spreads. This is where your induction tutor and lesson observations are invaluable. Recognise what you are doing to encourage a good learning environment and what you are doing to hinder it. Evaluate procedures for the register, lining up, the toilet and tidying. These need planning, training, practice and reinforcement, particularly for difficult times of the day.
Talk the problems through with someone. If you can't do this in person, try The TES online forum devoted to new teachers. It is helpful to think about outbursts of bad behaviour in terms of ABC. A is for the antecedents: the context and what happens before. B is for the behaviour itself and C is for the consequences: what happens to the people who have been sensible, as well as those who have misbehaved. While there's not a lot you can do about a child's behaviour in itself, you can work out the causes and the consequences.
Discuss the rules for the smooth running of the class with the pupils. You have probably already done this, but now you can revisit and refine things. Ask everyone (including adults) if they agree with them. Phrase them positively, perhaps as promises: we will listen when someone else is talking. Display them centrally, maybe with illustrations, and refer to them frequently: "Well done, you're doing rule four". Reward people who comply. Prizes can be anything from a smile to an award in assembly.
Think things through yourself before putting them into action. Being really firm and consistent with all pupils is vital. Don't fall into the trap of getting upset if kids don't seem to like you. Your job is to help them learn and behave, not to be their friend. Once you truly feel that inside, kids sense it, and ironically, seem to go out of their way to please ***
Sara Bubb's Successful Induction for New Teachers will be published by Paul Chapman later this month