Let's make a 2008 resolution, politicians and polemicists together. Let us renounce certain chippy clichés when talking about schools and social mobility. Let it become a mockable offence to refer — as Michael Gove MP did yesterday — to “the sharp-elbowed middle classes” who “colonise” the best schools. Let professors of education like Alan Smithers feel a stab of shame when they take an easy pop at academies getting “taken over by ambitious parents”. Let columnists beware of jeering at the “stupid spawn of the rich”.

Fun though it may be, it is all a wicked distraction from the main task: the improvement of all British schools — yes, all — and an absolute intolerance of the shoddy, the dull, the undisciplined and the woolly. The new figures hauled out by the Conservatives only reinforce a swath of others, which make it clear that, after ten years of Labour government, the gap between rich and poor children's attainment is actually widening.

But jeering at “sharp-elbowed middle classes” is a pure distraction technique, blurring the inconvenient truth that many of our schools are (if not actually chaos) intellectually unambitious and overburdened with irrelevant duties. It leads to such class-war fatalism as the ridiculous theory that places should be allocated by lottery: which implies accepting that some schools will always be rubbish, so let's spread the misery around by ballot.

No: it won't do. How dare a professor of education sneer at “ambitious” parents? Would he prefer it if they didn't give a damn? How dare a Conservative MP criticise conscientious middle-income parents as “colonists”, and suggest that their “sharp elbows” deliberately disable the poor?

Is it wicked for parents to want their children taught well in calm surroundings? Is it wrong to do your best? Most families are beset by worries about mortgages and redundancy and recession; they are not making war on the disadvantaged, but just doing what they can. They may kick off if rowdy children cause distraction and intimidation or sell drugs in the playground, but that is not class war. Any private school head will tell you that disruption and drug dealing occur in every echelon of society, and that parents protest just as fiercely when the Hon Freddie gives their child grief as when Charlie Chav does.

There are many roots of our school problem, and middle-class elbows are the least significant. One — fading now, thank God — is the legacy of the early comprehensive movement, which reacted against the cruel 11-plus by denigrating cleverness, precocity and academic passion in favour of mixed ability and rigid age groups. Then there has been a 25-year mania of central governments to interfere with every detail of the curriculum and keep moving the goalposts, thus de-professionalising and demoralising teachers.

Meanwhile a well-intentioned new sense of children's rights has led, through timidity and confusion, to an absurd erosion of teachers' authority — so now we need actual parliamentary edicts to enable staff to confiscate mobile phones in class. At the same time the mishandling of numerous cases of false sexual accusation, with adults guilty until proven innocent, scared many men out of the profession, creating a feminised, boy-hostile atmosphere. And now we have evidence that unpredicted, unmonitored and unresourced immigration leaves some schools unable even to teach the newcomers English.

On top of all that, there is a terrible fashion for loading on to schools the responsibility for inculcating things that are not facts or skills at all, but social desiderata — citizenship, sex education, diversity. This is largely a waste of time: note that while sex education has “improved”, teenage motherhood and abortion have climbed. It is now causing another ruction because of the equally loopy obsession with faith schools. Barry Sheerman, chairman of the Education Select Committee, is at odds with the Bishop of Lancaster who has (surprise, surprise) decreed that Catholic schools must not teach “safe sex” and contraception in a morally neutral manner, nor support Red Nose Day.

Mr Sheerman and assorted secularists are up in arms, asking why the state should fund “indoctrination” (do they think Muslim schools teach free love, then?). But they miss the main point, which is that this is froth. A State that really cared about the core of education, and its ability to raise and inspire poor children, would not faff about making schools teach citizenship and condom technque. If sex education is so important, force every 12-year-old to do a holiday course run by nurses. If citizenship is important, then support local youth groups instead of closing them down because their kitchen isn't up to scratch or they can't afford enough slow-motion criminal records

checks. Let schools just teach — properly, to an exam standard that cannot be fiddled, and with a focus on real subjects, whether that means astrophysics or practical woodwork.

I do not have the answer to every educational problem. Nobody does. I just know that one place where the answer certainly does not lie is in sniping at imaginary “middle-class” elbows. Stop doing it. Leave the poor sods alone. If all the schools were good, they'd soon stop manoeuvring, with a sigh of relief. Worried parental behaviour — if indeed there is anything wrong about it — is due to the deficit in the school system. It's a symptom, not a cause.

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