As temperatures rise, there are some classic signs that summer has arrived in schools. The caretaker at last considers turning off the heating (and he only put it on in January). New teachers have just discovered that their windows are painted shut to prevent pupils escaping.

One classroom I worked in was designed to be facing the sun’s glare for the entire day, and as summer kicked in I realised the head had had the windows locked down with five-inch screws. Her reason? We were on the first floor and she didn’t want children jumping to their deaths. Maybe it was a hint at the quality of my English lessons, but after a beer-related deal that saw my caretaker solve the problem with a hacksaw, the fatality rate wasn’t too high.

The main sign of summer in primary schools is that teachers will be having “the talk” with their classes. No, not that talk - they learn all of that from Big Brother nowadays. I mean the personal hygiene talk - the one about sweating in the heat and the importance of regular washing. The post-lunchtime stench in summer is indescribable to those who have never worked in schools. A sort of haze can form in classrooms, a manifestation of the smell that is so bad that it can obscure the whiteboard.

Anyone with a morbid fear of the unclean should never become a teacher.

Handing out weekly nit letters still prompts hysterical scratching among staff. A friend of mine once caught scabies from a child. A teacher probably sees more disgusting things in their career than a junior doctor does.

In my first term of teaching, the head drew our attention to an urgent item during a staff meeting. Somebody had been smearing their own (he hoped) excrement all over the toilet cubicles. He knew it was someone in Year 3 or 4 (the marks didn’t go that high up the wall) and he wanted us to check the children when they returned from the lavatory. “So what shall we do, Pete - sniff the hands of all the short ones?” asked an older member of staff.

The inability of many parents to send their children to school in clothes that have seen the inside of a washing machine in the past six months (teachers in more challenging schools will be familiar with the concept of “first up, best dressed”) can lead to dilemmas. One of my pupils once spent a morning making pancakes with the special needs co-ordinator. She asked him which special person he would like to share it with, and so I ended up being presented with a cold pancake, half-wrapped in school toilet paper, by a boy stinking of urine. Don’t worry, I’m not completely heartless. I did thank him and at least gave him the courtesy of waiting until his back was turned before pushing it gingerly with a pencil off the end of my desk and into the bin.

More from Henry in a fortnight