One of our younger students came up to me in the school library last week and asked whether he could ask me a question. ‘You just have,’ I said, deploying the dark sarcasm for which we veteran teachers are renowned.

‘Well, could I ask you another one?’ he said.

‘You just did,’ I said.

He smiled in that knowing way teenagers have for expressing the subtext of ‘I’ll play along for a while but have you any idea how irritating you are being and how unfunny this is?’

So there and then I short-circuited the question loop.

‘Fire away,’ I said.

‘Do you like being head teacher?’ he asked.

‘Yes,’ I said and before I’d had time to marshal any supporting evidence he unleashed his killer rejoinder: ‘I thought so,’ he said. ‘So, as head, what exactly do you do?’

I polished my response to questions like this from a childhood spent watching the classic sitcom, Dad’s Army. Captain Mainwaring was the pompous but ultimately well-meaning leader of a loyal platoon of Home Guard volunteers.

Whenever someone posed him an unwanted question he’d pause, puff out his chest a bit, and with no hint of being wrong footed he would say: ‘I’m glad you asked me that’.

I did the same. Then I decided to ask the student what he thought I did. He thought briefly. ‘You walk around a lot and talk to people’.

It’s not a bad summary, and I certainly wouldn’t be too unhappy if the words one day etched onto my mouldering gravestone were to say: ‘Geoff Barton. He walked around a lot and talked to people’.

I realise, however, that I’m one of the lucky ones. There are some school leaders facing much more challenging circumstances, especially after this summer’s results.

We were all warned that 2014’s GCSEs were going to be problematic. In August Glenys Stacey, Chief Executive of the exams watchdog Ofqual, warned parents, governors and parents to expect ‘big variations’ in grades. She said: ‘Comparisons between the national picture of results in 2013 and 2014 should be approached with caution, as you will not be comparing like with like.’

It explains why so many schools – state and independent – have been so cagey about GCSE performance this year, holding back information that they would usually make public at the start of term. Lots of us saw wild fluctuations in results.

But despite that warning some headteachers have lost their jobs as a result of poor results. School leaders – often key figures in their schools and communities – have disappeared from their school’s corridors, assemblies and websites.

One of the unacknowledged scandals of the current era of educational reform is the attrition-rate among school leaders. I know many of them in person. They are good people who came into the teaching profession with a sense of mission, moral fervor and a determination to improve the life-chances of young people.

Many of them chose to work in schools in challenging areas. They dedicated their working lives – and possibly too much of their private lives – to trying to make their schools better.

Suddenly these people are gone. They are education’s ‘missing’. And we hear little about the whole sordid business because the terms under which they disappear often requires them to sign a legal agreement not to discuss what has happened.

My instincts tell me that too many school leaders are being dispensed with by people lacking the same kind of integrity. Heads and deputies are handy scapegoats, ditched like football managers because of a set of disappointing results.

Too many good head teachers are lost in this way. Too many schools are destabilized as a result. And too many young leaders see what happens and are deterred from ever applying for headship.

I’m one of the lucky ones.

But in a different school, in another context, with Governors and staff and parents less supportive than mine are, perhaps I would turn into one of the missing.

I hope that one day someone exposes the sheer short-sighted waste of leadership talent these knee-jerk reactions represent.

Meanwhile, those discarded school leaders will be feeling wretched. They may have disappeared. But I can assure them they aren’t forgotten.

Geoff Barton is head teacher of King Edward VI School, Bury St Edmunds. For more on education, see our web page here