Go on Miss, d’you want a go too?” It’s Friday afternoon and I’m in a padded room little bigger than a broom cupboard in a small primary school with pupils for emotional and behavioural disabilities (EBD). It’s been christened “the anger room”, and I am at the end of a long week on supply.

The room is furnished with a huge stuffed clown joined together with Velcro, a playpen filled with balls and a glitter ball, with soothing music playing. It is used as a reward for good behaviour, and the favourite hobby of kicking the clown to pieces is one that David, 10, firmly believes I should share with him. “It’s great for stressheads like you, Miss. Go on, beat the clown up.”

“Sure, I can do EBD,” I naively told my supply agency the previous week.

“I’ve done special needs placements before. Is it just general cover they’re after?” The agency voice sounds dubious; do I know that EBD and MLD (moderate learning difficulties) are two very different ball games? I laugh (nervously), and say that as the children are only primary EBD, I’m sure I’ll be fine. And so I agree to travel from the predictability of mainstream national curriculum through the looking glass to the world of EBD.

Monday morning is unnaturally quiet. Two-thirds of my Year 6 class haven’t made it through the front door yet, as they’ve done a runner from the school bus parked in the playground. The minibus provides a vital door-to-door service as local taxi firms have banned most of the pupils.

Halfway through the literacy hour I spot them developing a PE curriculum all of their own - playing football on the roof.

The learning support assistants assure me this is nothing to worry about, that EBD should, in fact, stand for “every bloody day”, and that the missing group will make it to the classroom eventually. The head manages to coax them down, threatening them with losing their morning toast privilege if the roof stunt is repeated.

Lesson planning needs to cater for attention spans no longer than the flick of an eye. If you try spending longer on your delivery, you’re better off sitting on the roof with the rest of Year 6.

Tuesday dawns, and I’m in awe of the permanent staff, particularly the LSAs. I’m not trained in pupil restraint so rely on them to command and control any children who are a danger to themselves or others. They do it often, without batting an eyelid; the kids know it and hate it.

Inspired noises come from the music room with this afternoon’s brass lessons. It’s a surreal experience to hear a valiant attempt at the Titanic theme wafting through the sounds of chaos from the surrounding classrooms.

Darren, the trumpeter, makes his presence felt in a different way when he comes back to the classroom. He smacks one of the group over the head with his trumpet case, before sitting down to do his maths. Sam (the recipient) doesn’t seem bothered, saying it’s a good thing that Darren doesn’t play the euphonium any more.

Wednesday, and I discover the most enticing thing about this job is that you never know what to expect. Many of these children have unbelievably sad backgrounds, and their behaviour is hugely unpredictable. I remind myself of this as I dodge flying pens and well-aimed insults. The theme of today’s assembly is graffiti, relevant because large letters proclaiming “This scool is carp” were discovered on the school entrance this morning. Somehow the head keeps a straight face about the seriousness of the offence and explains that, as anyone can walk past, what impression does the graffiti give of the school? Wayne pipes up: “But Sir, if anyone could have seen it, then surely anyone could have done it.” The head says that, somehow, something tells him someone in the room is responsible.

Thursday is uneventful. A suspected outbreak of scabies means two livewires from my class have been kept at home. I’m reliably informed by Sam that Darren isn’t in as he has rabies, and I’ve got to wash my hands lots as his mum says it’s very contagious. I give up trying to explain the difference between scabies and rabies. I’m so impressed with my charges I decide to let them go out for the bus early, only to be told that last time a supply teacher did that, they set a hedge on fire. Panic-stricken I run out, but they’re just relaxing, lying on the ground by the gate. Jeff says he thinks I’m “a bit mental”. I take it as a compliment.

The writer is an ex-mainstream teacher in the south of England, working on supply. She wants to remain anonymous