I was reminded, when I heard this, of Mr Jones (let’s call him that), sadly dead now, who had taught in the same classroom of a Midlands secondary school for almost the whole of his career. His teaching methods remained largely unchanged throughout that time.

A great believer in discipline, Mr Jones saw himself as a bulwark against a rising tide of anarchy. He liked to take assembly, because it gave him the opportunity to bring the whole school to heel a bit.

The traditional definition of assembly - “A hymn, a prayer and a bollocking” -might well have been coined with him in mind.

His way of encouraging hymn-singing, for example, was to stand, frozen-faced, arms folded, silently listening to what amounted to tentative groaning set to music. Then, after a verse or so he would shout, “Stop!”

and deliver one of a selection of diatribes, the best one being “You can make plenty of noise for your favourite rock groups. Now let me hear what you can do in the presence of Almighty God!”

So what’s to be done about dinosaurs? The first thing, I guess, is to question the label. We’re pretty quick with labels and stereotypes, aren’t we? Once Mr Jones or the teachers in their coasting school are labelled as “dinosaurs” - or simply as “negative people” or “obstructive”, or “don’t want to know” - then the danger is that everything they say and do will be seen in that light.

From that point the whole thing becomes self-fulfilling - exactly as it does with children. For wise words about this, look at the “Ask Siggy the Shrink” website, where someone pleads, “Help me with people who are ALWAYS negative.”

The answer includes this advice: “Remember that when you use big generalisations - like always, never, everybody, nobody - in what you say, they usually reflect big generalisations in your thoughts. Big generalisations are rarely accurate, and they can hide the details that would reveal the truth.”

So part of the answer is to look beyond the catch-all judgement, and seek out the rather more complicated person behind it.

That was what Mr Jones’s last headteacher before his retirement did when she arrived. She listened to the warnings about him. But she kept on listening, and gradually learned a few other things about this dinosaur.

That the parents respected him, for example. And, rather to her surprise, that the children quite liked the disciplined peace of his classroom, where, behind closed doors, he exhibited a degree of gruff kindness rarely seen in the staffroom (which he hardly ever used) or the assembly hall.

She discovered that he was in demand by local churches as an excellent lay preacher. She noticed, too, that after school was over, he was often still in his room with a group, running, in effect, an unofficial homework club for children who found it difficult to work properly at home. (He didn’t talk much in these sessions, preferring to get on with his own work. The striking thing, though, was that the children clearly felt secure there.) Mr Jones, she realised, though entirely comfortable in his classroom, felt resentful and threatened by changes outside it. What the head had to do, instead of confronting the aggression of this “dinosaur”, and adopting the “shape up or ship out” strategy urged upon her by others, was build up his confidence and convince him that he had a significant place in her vision for the school.

It was, of course, easier to have the thought than to carry it through - but that sort of challenge is what leadership is all about.

So, over a couple of years, she made a friend of Mr Jones, cashing in on his disciplinary skills, but encouraging and coaching the kindness that was always there. She sat in his church and heard him preach, and pointed out the way that his skills could be used in school. She made his homework club official - as, inspirationally, “Study time with Mr Jones”.

So, for the final years of a long career, Mr Jones was rediscovered, both by others and by himself.