I'm on placement at a challenging school and am teaching three classes, two of which are known to be disruptive. But it's the "nice" class, a high-ability Year 9 (S2) group, that seems to have turned on me. One girl has complained to other staff that I'm "picking on her" and that the rest of the class agree (apparently). They swan in smirking at me, in a way that seems prearranged, and one of the boys tries to take apart every comment I make.
What you said
It sounds like they have noticed you are a bit nervous and are trying to push it. Children this age can be unpleasant to teachers - they often seem to get a kick out of making you feel uncomfortable. If they try to intimidate or upset you by picking up on little things you say and twisting them, I would defuse it by looking at them, pausing and waiting. They will almost always quail. If they don't, explain what you meant in a literal way and be slightly patronising.
The expert view
Unfortunately this is a common situation for new teachers. They start off with a class that resents change and the introduction of a new authority. Automatic deference to rank is dead, so the pupils expect you to "prove yourself".
This means that many children will take the arrival of a new teacher as an opportunity to do as they please. They know, or believe, that you won't be there for long, are a little uncertain and might not know the ropes so well. And many will exploit that.
The sad thing is that many nice kids will do this, too, especially if they are triggered by strong personalities in the room. Because they don't see you as an authority, attempts to modify their behaviour by issuing instructions or consequences can lead to confrontation.
The key thing you need with these pupils is persistence. You also need to be consistent, have clear ground rules and establish consequences for bad behaviour. If someone repeatedly disrupts your lesson, have them removed to the exclusion room.
Tell them what will happen if they cross the line. Then make sure it happens. If they fail to attend detentions, escalate your response and get others involved.
Tom Bennett is author of The Behaviour Guru. http:behaviourguru.blogspot.com
Post your questions at www.tes.co.ukbehaviour.