It is the biggest and most intractable problem in British education: the yawning gap in achievement between middle-class and disadvantaged children. Despite huge efforts over the last two or three decades, we have not managed to close that gap.
Indeed, in some ways it has got wider. As motivated, middle-class children have got better and better at jumping through the assessment hoops, all too many of their disadvantaged peers have switched off and given up.
Now we face some years of severely squeezed spending on schools. Will that make the problem worse? Deputy Prime Minister Nick Clegg says the pupil premium will help mitigate the cuts and could really help to boost the performance of disadvantaged pupils. But it all depends on how schools spend the money. If most of the efforts made during the years of relative plenty have not made an impact, I doubt if aiming more of the same at the poorest children will make much difference. It is time to be a bit more imaginative.
At the moment, we provide education to young people through academic subjects, in a school setting, to a very rigid curriculum. In too many schools, for too many children, education has become a joyless and alienating chore. They opt out, either physically by playing truant or mentally by zoning out. They need to be offered opportunities that engage and excite them and bring them back in.
My experience since leaving the civil service has convinced me that the best way to do this is through the creative arts. As vice-chancellor of the University of the Arts in London - the biggest centre of art and design education in Europe - then as co-founder of Artis, a company that provides performing-arts teaching in schools, and now as chairman of Filmclub, a national charity that provides children with the opportunity to watch great films in school, I have seen at first hand how the arts can switch young people on to education in a way that nothing else can.
At Filmclub, we have recently received hard evidence of how far-reaching the impact can be. In a survey completed by nearly 1,400 teachers who run film clubs, many of them heads, more than nine out of ten said they were effective at engaging pupils who did not take part in other activities and that they increased participants' enjoyment of school. Most tellingly of all, nearly six out of ten agreed that film clubs were effective in closing the gap between the highest and lowest achievers.
How can watching a film a week, and then discussing it, have such an impact? Part of the answer lies in the medium: film is especially suited to drawing in children from all backgrounds. But the main answer must be that taking part in activities such as film clubs, drama clubs, school plays and choirs opens up access to culture for those who might not otherwise benefit from it. Many of the children who join film clubs have never been to the cinema. Some have never even seen a film all the way through.
As Sir Alasdair Macdonald, headteacher and transformer of Morpeth School in the East End of London, has said: "If we want to narrow this educational disparity (between rich and poor children), we need to give children from disadvantaged backgrounds what their middle-class counterparts already get beyond the classroom - culture, books, cinema, theatre, art."
That is why the arts should be a central activity at all schools - not considered a bit of froth or an add-on that can be cut when the going gets tough without anybody noticing. For every child, rich or poor, gifted or struggling, they make school a more inviting and inspiring, a more truly educational place. For many, they are the path to a future job. But they are especially crucial to children from deprived backgrounds. If they don't have access to the arts at school - don't have the chance to act, to dance, to sing, to see the best of world cinema - they may never catch up with those self-confident, middle-class children who take such things for granted.
So I hope ministers - and schools - will resist the temptation to retreat back to a core of basic skills. The core is already too narrow. Let us put the arts back where they belong: at the heart of education. If we don't, the achievement gap will never be closed.
Lord Bichard was permanent secretary at the Employment Department and then the Department for Education and Employment from 1995 to 2001. Next week, he will chair a one-day conference in London titled "Closing the Gap", sponsored jointly by Filmclub, Save the Children and The TES.