Never in all my time in the classroom did I feel I was a natural-born teacher. In so far as I succeeded it was by making many mistakes of my own, observing the mistakes of others, and trying to learn from them. Some of these examples may have a flavour of a different era, but I believe they hold true - so don’t make the same mistakes I did .

Futile threats of retribution

“Right! If anyone does that again I will .” Well, go on then, what? Burst a blood vessel? Call down fire and brimstone? Fall kicking and screaming to the floor?

Threats are easy to make, and sometimes work in the short term. But scary ones are difficult to carry out. So what you usually settle for is something pretty safe, such as: “If you carry on like this I am going to be very annoyed!”

As if that’ll put the fear of God in them.

On the whole it is probably best to avoid threats altogether. They tell the class that you aren’t confident enough to apply a sanction without warning. It’s better to make both praise and punishment immediate and confident.

The `next person’ trap

“The next person who talks is going in detention.”

Oh no, it’s Samantha - I was hoping it would be Darren. Maybe if I pretend I didn’t hear her, Darren will talk in a minute and I can catch him.

“Please, Sir?”

“Yes, Jack?”

“You said the next person who talked would go in detention. Samantha talked, Sir. I heard her.”

“Did she really? I’m afraid I didn’t hear. Samantha! Take care. You know the rule.”

“I’m sorry, Sir. I was just asking Gurdip if I could borrow his .”

“DARREN! DID YOU SPEAK?”

“Me, Sir? No, Sir!”

“Don’t lie to me, boy. I saw your lips move. You know the rule. Detention.”

“Sir, it’s not fair, Sir!”

Setting work without thinking of the marking load

“OMG, Facebook friends. You should see the marking I’m taking home this weekend. I’m grounded for the duration.”

Blame yourself, I say. What you did was forget that marking has to be considered at the planning stage. The question to ask is: “What marking will emerge from this lesson? What can I do to reduce it?”

Be aware, too, that there are ways of marking other than just wading through piles of work writing comments and adding grades. This document from the Highland Council is a useful summary of alternative assessment strategies: bit.lyJHILxS. If you plan with care, you will know what each lesson will produce in terms of marking, and you can arrange it so the heavy marking nights come at the least inconvenient moments.

Putting on a video and relaxing

A teacher, much more senior than I was then, arranged for his class and mine to see a geography-related educational video. We sat at the back. As soon as we switched it on, they switched off, talking and laughing among themselves.

“Don’t worry,” said my supposedly wiser colleague. “Something like this has to keep its own discipline. If it can’t keep their attention we can’t do anything about it.”

That’s nonsense, of course. He just wanted half an hour of time out, and given his job who can blame him? What we should have done was watch the video first, fillet it for the useful bits, prepare some questions, maybe give out a worksheet. My own mistake was in not winning brownie points by doing that in advance.

Shouting

I learned a lesson about shouting early on from a difficult secondary school class. Bad girl Margaret was playing me up. Driven to distraction, I yelled “Margaret!” At the same time I was aware of a sort of stereo effect, and the whole class dissolved in laughter. It took me a moment to realise that one of the lads, watching my face closely as I built up to my explosion, had shouted “Margaret!” precisely in unison with me and at exactly the same volume. Dignity out of the window yet again.

We all know we shouldn’t shout. But we also know how hard that is under pressure. How to tackle it? Deal with it like any other habit, by setting yourself achievable targets. Not “I will never shout again”, but “I will get through this lesson without shouting.”

Using certain subjects as punishments or rewards

I actually heard a colleague say this: “OK, that’s it. You’ve lost PE. We’ll do maths instead. No, it’s no good saying anything. I warned you.”

Consider the messages this teacher has now sent out, none of which live up to professional standards:

- Physical education is not so much a lesson as a period of relief from proper work.

- Maths is hard, unpleasant and boring.

- The timetable can be manipulated by you for reasons that have nothing to do with learning.

- The behaviour of a section of the class can provoke you into disrupting everyone’s day.

- You don’t care that an unknown number of children hate PE and are relieved to be missing it, or that others love maths and relish the chance to do more of it.

Not being frank with management about mishandling a behaviour problem

Twice, while I was a senior member of staff, colleagues came to me to say that they had lost their temper with a child. One had slapped a boy’s face. The other had clutched a lad by the front of his jacket and backed him, roughly, into the wall.

Both sets of parents arrived to complain. However, because the teachers had been prompt in coming to me and entirely frank, I was able to keep everyone on-side. I was equally frank with the parents, each of whom recognised three crucial truths: that their child was quite capable of driving any adult to distraction; that teachers are human and sometimes do things they regret and that we took the matter seriously. Most importantly, we had built up trusting relationships with each other and with the families.

Starting the day ill-prepared

“Come on! Come on! Get a move on! Go THROUGH, you fool! It’s still on amber!”

Right. Made it to morning briefing. Don didn’t spot me sneaking in. I’ll stand at the back next to Megan.

“Pssst, Megan! What day is it? Yes, Megan, I am serious. No, Don, sorry, I wasn’t asking a question. All fine, Don, thanks. Sorry.”

It would be Thursday, wouldn’t it. Double period with 9K in the huts. Must go to the toilet first, though, and pick up a coffee. God, I’m not as fit as I was. This campus gets bigger every day. Hell, I can hear them already.

“OK, I’m coming, for God’s sake.”

Ah. They have suddenly gone quiet. Must have spotted me running across the tennis courts.

“Right, 9K. Get out your . `Oh, hello, Don. Didn’t see you there. Yes, yes. Sorry I’m late. Misread my timetable, I’m afraid. Yes, again, apparently. But I’ll just carry on now, will I? See you in your office? At what time? Of course .’”

Asking poorly worded questions

“OK, 5W. What do you not find on top of a mountain?”

That was an example of a poor classroom question used by one of our college lecturers. The fact that I remember it after so many years shows how important a message it carried. Classroom questioning is at the heart of the pedagogic craft, part of the process of guiding children towards learning. Poor questions are either so open-ended as to be meaningless, too difficult for the class or too tightly framed.

Good questions are encouraging, accepting, well-distributed, inclusive, differentiated . I could go on. For good tips, see Teachers TV’s advice on the TES website: bit.lywV4CpF

Sitting down too much

In my early days I made the mistake of staying behind my desk while children queued patiently to see me. Gradually I disappeared from view behind them. If something unexpected happened - a call for help, the entry of the head - I would burst forth like Orca the killer whale emerging from the deep.

By contrast, in the Birmingham secondary where I later worked, the head of maths, who suffered from a debilitating back problem, would often teach lying flat on the broad window ledge of his room. The pupils’ respect for him was such that they were ready to pay attention regardless.

What does that prove? Only that when it comes to judging the effectiveness of a teacher, whether they sit, stand or lie probably isn’t the main defining characteristic. Try telling that to inspectors, though.

Assuming that what works in one school will transfer to your new job

Over six years working with some difficult children in low-ability classes, we got to know each other pretty well. They knew where the boundaries lay, when things were serious and when they weren’t, when it was OK to be cheeky and when it wasn’t.

Then I went to another school. In my first lesson with bottom-stream 14- year-olds, I invited them to leave their desks and sit in a circle so that we could just chat. I failed to realise that this was a signal to them that I was Mr Softie. It took me ages to get back on top. A neutral observer would say I never did quite manage it.