I have a year eight class who, for the most part, I get along fine with. But a couple of months ago a new girl started in the class and now it's hard work because she's always causing trouble.

She was expelled from her previous school, I'm not sure why. Her main crime is constant, and I mean constant, talking. But that's not the sort of thing people get expelled for, unless she literally talked a teacher to death - which doesn't seem impossible.

Today she was on top form: non-stop (one-way) conversation with the girl she sits next to, drawing on her whiteboard when she was supposed to be doing divisions, chewing so enthusiastically that I could actually see the gum and then denying its existance. I can understand pupils misbehaving but I'm completely baffled by them denying obvious truths. I wouldn't expect them to believe I have eyes in the back of my head, but I do expect them to realise I have them in the front.

I had to send her out and she complained saying that she shouldn't have to do maths anyway because her dad says it's pointless. I believe her too. I sort of feel a bit sorry for her because I don't think she's misbehaving on purpose, it's just that she's never been taught why it's wrong. Which means she's going to be in constant trouble at school and grow up thinking everyone's out to get her. Poor girl.

I think I'm turning soft.