I have been struck down yet again. I don’t know why people get so worked up about killer superbugs - schools are breeding grounds for some of the most lethal spores known to man. Were a terrorist group to release anthrax or sarin at St Brian’s, no one would notice because we’ve survived much worse.

In fact, if our bursar, Amy Studds, had her wits about her, she wouldn’t mess about with bids for standards fund cash or laptop grants, she’d go straight to MI5 and offer to sell them swabs of the Year 8 classroom walls as weapons of mass destruction.

So I’m dying, but have struggled into work to face a heavy teaching day and the indifference of staff and pupils. I explain to Judith Crock, my head of department, that I am suffering from what feels like a combination of dysentery and the Sars virus and there’s a possibility I might not make it in tomorrow. She finally looks up at me when a bead of sweat from my forehead splashes loudly on the copy of You and Your Dog she is reading during her coffee break. She mutters something about working through the pain barrier and not encroaching on colleagues’ non-contact time as she dabs at the soggy page with the sleeve of her cardigan. I point out that she herself has been a rare presence during my two terms at St Brian’s, but she just smiles and says: “But Miss Casement, you’re an NQT.”

That evening I know I shall have to defy Judith Crock. So I spend four hours preparing cover work before collapsing into bed. I set the alarm for 5am to give myself time to organise my absence.

My first task in the morning is to phone the cover line. Why do I feel like a criminal? I dial the school number, ready to leave my deathly message on the answer machine, but am shocked to hear a real voice. “Hello? Nigel Horsmel here.” Christ, the acting head. I check my watch - it’s 5.30am. I contemplate slamming the phone down but garble something about a chest infection instead. Horsmel tuts and the line goes dead.

Next, I put the finishing touches to my worksheets, email them to school and settle down to a few hours of Dale Winton and David Dickinson. But I can’t concentrate. It’s not the illness, but the knowledge that I’ve got to go in tomorrow and face the poor bastard who’s been covering 9C. By nightfall this thought has become an obsession, the guilt overwhelming. I barely sleep all night.

The next morning I am the pariah of the staffroom. Head bowed, I shuffle to my pigeonhole and attempt a half-hearted cough. I can feel the stares following me. “Selfish cow!” I hear someone mutter. The pigeonhole is stuffed with 9C’s cover work. Strangely, the assignments do not resemble the carefully planned tasks that I set. I groan as I read the title, “What does history mean to you?” Oh no, an open writing task. There is no signature on the top sheet, just the words, “Thanks for leaving me with the group from hell. Left you some marking. Enjoy!”

Glumly, I make my way to the hut. A window has been smashed and several of the wooden chairs are in splinters. Wall displays are now floor displays.

So this is the price of a day off: three hours’ sleep, the hatred of your colleagues and a wrecked classroom. Sam Skinner from 9C appears at the door. “That was the best lesson ever yesterday,” he pants. “Can you be away again, Miss?”

Next week: Bye-bye tracking data