When I was a pupil at Glenalmond in the 1970s, no one had heard of such a thing as a parental complaint. The notion of it was inconceivable - as unthinkable as blowing up the school or shooting my headmaster with a gun from the armoury.

And, actually, when I think about it, the idea of partnership with parents – which is now so integral to all that we do – was still a pretty nebulous idea even when I began teaching in boarding schools in the 1980s.

We would, of course, see the parents from time to time to deliver a few well-chosen words about their progeny’s academic progress – but mostly they were just the owners of large, shiny cars that arrived in fleets at the beginning of term or sat under impressive hats on speech day.

Twenty years on, our world could not be more different. In all our schools, we crouch, sometimes almost fearfully, as the helicopter parents drone overhead. With each year that passes, the drone seems to grow louder – to the point where we feel we can sometimes hardly concentrate on our teaching or make ourselves heard.

So what are helicopter parents? They are the ones who pay such close attention to their children that they rush forward to try to prevent anything bad ever happening to them. Nor will they allow their children to learn from mistakes – sometimes even contrary to the children’s own wishes.

Of course, it is natural for a parent to be concerned, and to contact the school and intervene when necessary, but the helicopter parent is simply not ready to recognise the bond of trust that exists between schools and their customers. Indeed, helicopter parents are often blessed with a sense of (almost papal) infallibility as far as their own opinions are concerned; or, they will cast themselves in a heroic mould as defenders of the faith against those who they think may be tyrannising and oppressing their (allegedly) helpless offspring.

I did not come across the modern helicopter parent until I became senior deputy head at a thriving co-educational school in the Midlands. I soon began to notice that in a school of nearly 900 pupils, approximately 20 helicopter parents were beginning to consume more and more of my time.

Most of this contact was by phone; a fair amount by e-mail; and then there were the face-to-face meetings to prepare for and record – meetings that could leave you feeling older and somehow diminished as you battled to convey straightforward points.

Sometimes, in my experience, the parent wants just to pick over a detail: the history of a missing hockey stick or the possible implications of one phrase in a subject report. More often, however, the helicopter parent will be standing firm on what he or she believes is an issue of “principle”.

A girl in year 9 is seen smoking by two members of staff and it is an open-and-shut case that she has broken school rules. However, it ceases to be an open-and-shut case when the helicopter parent phones you to say that his “little girl” was only “holding the cigarette” for a friend who was standing beside her at the time.

You are sceptical about the claim, but you go back to the members of staff who saw the girl to check again. They are adamant that the girl was actually smoking the cigarette. You return to the helicopter parent with the update and – surprise, surprise – they tell you that the two members of staff are “mistaken” because (and you frequently hear this) “my daughter has never told me a lie in her life”.

From there, of course, the results are predictable. You insist the child must be punished; the helicopter parent will not “support” it; there is a formal complaint; and, after a few hundred more trees have been felled in documenting the process from A to Z, the helicopter parent’s grudge against the school has grown apace, meaning that it will be even harder to give the girl a sanction for anything.

Let’s take another example – the kind of “minor” incident where, say, a group of year 9 boys are discovered pelting each other with fruit in the school gardens. One of them gets an apple in the eye that causes an unsightly bruise. This, unfortunately, is the son of the helicopter parent (though the incident would, or course, be unfortunate no matter who the boy’s parents were) who demands that the school sanction the others.

After you have looked at the boys’ written accounts and the eyewitness testimonies of three girls who were watching, it is obvious that the helicopter parent’s son not only initiated the apple fight but was also the star performer. You phone the helicopter parent to relay the substance of this and are (vigorously) told that the boys are covering their tracks and that the girls who watched are “unreliable”.

The helicopter parent then demands to see the witness statements under the terms of the Freedom of Information Act. When you explain that the terms of the act do not apply to the case, he says he will go to “the press”. At which point there is nothing to do but shrug your shoulders for, unless the media have taken leave of their senses, the story of the apple fight is unlikely to make the front pages.

Are these, then, exceptional cases? In my experience, they are not daily occurrences, but they are becoming more common. And even though most of our parents are supportive and kind, the proliferating number with an almost crazed sense of entitlement is forcing us to create a new culture in order to deal with their challenge.

Increasingly, the measures we take – the rewriting of our (now 10-page) mobile phone policies, our insistence on the recording of all “sensitive” conversations, our redrafting of the complaints procedure – all feel a bit like the building of fortifications, behind which we are destined only to shout at each other.

The helicopter parent is a threatening reality, but far worse is what we, by way of response, are doing to ourselves – and, of course, to our pupils. Though it feels as if we are the victims, it is the children caught in the middle who will end up, once again, copping the worst of the flak. Alistair Macnaughton is headmaster of King’s school, Gloucester

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