In October 1982, I first stood in front of a class (discounting the time my P4 teacher let me bring in some kit from my chemistry set to demonstrate an experiment). It was the second day of my placement, a Tuesday. On the Monday, I’d arrived and was taken to meet the head of physics, a kindly old geezer who was probably several years younger than I am just now.

“I won’t have to take any classes today?” I asked.

“You know what he just asked me?” said the principal teacher when introducing me to the rest of his department. He then assumed a voice of appalling, quavering nervousness and repeated my query about taking classes. I felt my head pop, tortoise-like, into my brown sports jacket. Why had I asked such a bloody silly question?

Not for the first time, I was beating myself up prematurely, for 24 hours later the head of maths announced that he had a dental appointment last thing, he’d leave work and I could supervise his class. I was too naive to realise that this really wasn’t on, so clad in the brown sports jacket, possibly the dullest garment ever worn by anyone, I took his class, sort of. If you learn from mistakes, I gave myself an immense number of learning opportunities during that first lesson.

I like to think that if you drew a graph of “number of mistakes made by Gregor in teaching” versus time, it would be an exponential decay curve. Like a graph of radioactivity, there would be spurious high and low readings and it would never quite get to zero. I like to think that, but it wouldn’t.

There would be a sharp upswing at the point when I came back from my secondment in 2006. In fact, part of me wonders if I was just unlucky with an awkward set of pupils. Another part asks itself what effect a very sad event taking place in our extended family was having, but that same part also finds the notion of attaching any blame to these particular circumstances almost blasphemous. Whatever was going on, there were times when my anger at certain children was not theatrical. I lost the rag. Gave bawlings out in the corridor. Mistakes.

I like to think that I had things back in hand when I moved on to my current job, but I will always wonder if I’d just reached a point on the graph where the reading shot up due to a spurious burst of metaphorical cosmic rays. I can joke about brown sports jackets, but not about this low time. It won’t go away. You know what? Given that I still work with teachers, perhaps that’s a good thing.

Gregor Steele no longer owns any sports jackets

Scottish Schools Education Research Centre.