I am on the overcrowded bus, wedged between a greasy window and an overweight man in a puffer jacket. The bacon sandwich he is eating is both enticing and nauseating as we jerk through the housing estate. I clutch my leather briefcase nervously, hoping this route will take me near enough to the school to be on time for the 8.30am start.
This is my first time here and I start to wonder what the kids will be like. It isn't long before I find out: at the next stop, a vast crowd of blazered schoolchildren storms on to the bus, barging and jabbering. Oh dear, they look lively – very lively – I think to myself. I hold my newspaper up to my face and start to perspire. Have they seen me? I hope not. Note to self: Supply teachers should not take buses with their pupils.
As we arrive in front of the bleak campus, I slip off the bus unseen (I hope) and walk to reception – the head of cover is waiting, a pen and notepad in hand.
“I’m from the agency, science cover,” I say as enthusiastically as I can for a man traumatised by public transport, “Where should I go?”
“Well actually, we were looking for you to do some maths, English and geography today,” she chirps back with a hopeful expression.
My heart sinks – this could all go so very, very wrong, I think. What do I know about Romeo and Juliet and oxbow lakes? I’d surely have better luck teaching Sanskrit.
“Ok,” I say, hoping my inner polymath will emerge in the next four and a half minutes before lessons begin.
As it turns out, I’ve never had so much fun teaching in my life. In geography, I have the pupils in stitches as I do an impersonation of a mid-Atlantic depression (laughing with me or at me?). In English, a comparison of war poetry turns into an edgy discussion about the allure of Syria for radicalised Muslims in the UK (don’t tell the Prevent strategists). Maths just seems easier to teach than science: the kids enjoy the simplicity of its rules and don’t give me that puzzled look you get when teaching about combustion or evolution.
The spontaneity of it all gives me a bit of a headrush. My years staring down the barrel of a gun as I “delivered” science to unwilling teenagers fade away. Suddenly, I can be myself, and the kids warm to me. The “teachbot” in the goggles is no more. I’m suddenly a sort of Stephen Fry of the comprehensive school, bringing knowledge and avuncular amicability to the classroom. It’s enough to get you into your tweed jacket.
I get on with the kids, too. They seem to enjoy a change of teacher for the day. I certainly enjoy the change of subject.
Who knows, I might even take the bus again tomorrow.