I feel like a teenage mother. I only finished my induction last summer, but here I am mentoring my very own NQT. Judith Crock’s walking accident and the untimely death of her pet terrier mean that she’s unlikely to be back atSt Brian’s for some months. So, in my first term as a fully qualified teacher, I am acting head of history. And my main area of responsibility seems to be Angel Montague.

Angel has taken to following me around school, a shiny ring binder marked “Career development profile” tucked under her arm. When I arrive in the morning she’s there waiting for me in the staffroom; when I leave a classroom there she is, prowling the corridor, ready to pounce with a question about the latest QCA directive or a suggestion as to how we can improve our differentiation strategies with the Year 10 low achievers. Next she’ll be demanding to know what’s happened to her 10 per cent reduced timetable.

I know, because these are the questions I asked last year. At least, I would have liked to ask them, but couldn’t because Judith Crock was off sick most of the time. I didn’t have anyone to look after me, so why should I look out for this pale young thing who has a pink teddy bear key-ring hanging from her rucksack and photos of her kittens stuck on the front of her planner? I want to grab her and tell her she’s been the victim of a cruel hoax: “Don’t let them do to you what they did to me! Run, Angel, run!” But I don’t. I just tell her that, yes, dealing with passive-aggressive students is indeed an important aspect of behaviour management and we must have a chat about it when I’ve got my next free period. Which I estimate will be some time next March.

As I sift through the pile of paper in my pigeonhole, doing my best to ignore Angel’s endless questions, I find a memo from the head, Dr Scarlett, asking me to attend an interview for my current post. I am taken aback as St Brian’s has traditionally adopted a rather relaxed attitude to recruitment. Supply teachers who haven’t given up by lunchtime are usually offered full-time jobs. And last year we had an Aussie assistant head called Kirsten who was here on a working holiday. She did a great job overseeing behaviour and inclusion, but disappeared suddenly in May, only to turn up on a podium in Athens as bronze medallist in the women’s freestyle wrestling competition.

As I’m staring at the memo I get a tap on the shoulder. It’s Miranda, the school secretary, smiling conspiratorially. “Don’t worry, Charity, you’re a shoo-in. There was an external candidate but I sent him a copy of our last Ofsted report and he pulled out.” She winks and scuttles off.

Five minutes later I am in Dr Scarlett’s office being congratulated on becoming the official head of history, and there are handshakes all round.

A sweaty palm clutches mine. It belongs to Nigel Horsmel, the deputy head and all-round creep. I recoil as he draws closer to me.

“You’re almost one of us now, Charity,” he leers. I feel very faint.

Next week: Just blow into this bag, sunshine. Charity Begins: Adventures of an NQT, Charity Casement’s diary of her first year at St Brian’s, is available from TES Books, pound;2.99. Tel: 0870 444 8633 or visit the TESBookshop at www.tes.co.uk