I recently met a bright 17-year-old from a working-class background who attended his local comprehensive in London. He was funny and articulate. I asked whether he or anyone at his school had considered applying to Oxford or Cambridge. He laughed: “We don’t think it’s for people like us.”

It is a reaction I hear often and helps to explain a sad waste of talent in Britain today. Last week a study showed that just 200 elite schools accounted for one third of admissions to the top dozen universities and half of all places at Oxford and Cambridge. The remaining 3,500 schools and colleges account for the other half. It is neither fair nor sensible.

While others are tempted to pin the blame on biased universities, I believe there is something more deep-rooted at work – a culture of low aspirations shared not just by students, but in many cases by their parents and teachers, too. There are many excellent teachers doing their best for the students, but it is a disturbing fact that some bright pupils are actively discouraged from reaching for the top.

I have long taken a personal interest in this question. Last week’s university research was carried out by the Sutton Trust, the educational charity that I founded and chair, in an attempt to widen the circle of opportunity.

I know first-hand how important aiming high can be. I grew up on a council estate in Yorkshire where I was lucky enough to pass the 11-plus. Until this point nobody had suggested I might go to university. My parents encouraged me to work hard, but university was a world away from their own experiences. My father found a better job and we moved to a detached house in Surrey and I went to Reigate grammar school where, if you did well, you were encouraged to go on to university. Then, in another upwardly mobile shift, we moved again and I ended up at Cheltenham grammar, where bright boys were encouraged to aim for Oxbridge.

If my family had stayed in Yorkshire I would almost certainly not have gone to university. If we had stayed in Surrey I would not have gone to Oxford. Higher aspirations changed my life. Oxford led on to the London Business School, to a career in consulting and private equity. I never looked back.

That was decades ago; I would have hoped that things had improved. But they have got worse. Sadly, in Britain today, aspirations are rooted in class.

According to our research, parents in professional and managerial occupations believe that their children will go on to take A-levels, to attend good universities and end up in high-paying careers. It becomes a self-fulfilling prophecy. Those in lower-paid jobs, by contrast, are likely to think that their children will leave school at 16 and go into routine employment.

You might think the classroom would act as a corrective. But all too often low expectations are reinforced by our socially selective school system.

The Sutton Trust has surveyed 20% of the teachers in state schools who advise students on university – and more than 80% of them said they thought their pupils would find it difficult to fit into the top universities, particularly Oxbridge.

Hard-pressed teachers face many other pressures and in some cases lack the confidence and know-how. Parents, meanwhile, are frustrated. Some even tell of instances where their children have been told not to bother applying to Oxford or Cambridge, despite being qualified.

That is why the Sutton Trust has announced that, together with its partners, it will spend £10m over the next five years to expand its sponsorship of outreach programmes such as summer schools to dispel the myths around the top universities.

Even then it can be an uphill struggle. There is a shortage of applications from boys (less than a third). Many of those who do come hide it from their peers for fear of being branded a “swot”.

This could not be more different from the attitudes of young people from independent schools. Their classmates are aiming to be bankers, lawyers and doctors. These children are articulate and confident. They have every reason to be. They have spent summers travelling overseas and undertaking internships at prestigious firms, not stacking shelves. Going to Oxford or Bristol or Durham is the natural next step.

It is no wonder that social mobility has declined in Britain and we languish at the bottom of the international league table. Also, the relationship between children’s educational performance and their family background is stronger here than anywhere else in the developed world. If you are born poor, your qualifications will reflect the fact and you will remain poor.

Raising the aspirations of young people – as well as parents and teachers – is half the battle. The Sutton Trust is trying. We work with children in the early years, through school and into further and higher education, to provide the sort of support and encouragement to nonprivileged youngsters that better-off families and high-achieving schools provide as a matter of course.

More is needed. Why not open up leading private and state schools to those from nonprivileged backgrounds, as has been done successfully at the Belvedere school in Liverpool and Pate’s in Cheltenham? We should learn from successful schools and extend the opportunities they offer to all.

Children’s futures should not be down to luck: we must ensure that all young people have access to real educational opportunities. That is a very modest ambition for a country that prides itself on fair play.

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