“It’s not fair.” These are quite possibly my children’s favourite three words. But it isn’t only children who favour them. They capture how most of us feel about society. According to the government’s latest Social Mobility Barometer poll, three-quarters (74 per cent) of the adult population believe there is a “very” or “fairly” large difference in the opportunities available in different parts of Britain today.

What’s more, young people are the least likely to think that everyone in Britain has a fair chance to go as far as their talent and hard work will take them.

These beliefs are problematic for teachers because they are completely at odds with the narrative that we are constantly trying to push in schools: that if you try hard and have the right “mindset”, you can go on to live a successful life no matter where you come from.

Unfortunately, the experience of many young people is that this narrative simply doesn’t hold true. In a perfectly fair society, a child born to a poor family would have the same chance of financial success as anyone else. This would mean that a poor child should have a one in five, or 20 per cent, chance of getting into the richest fifth of the population.

The reality is that their chances are less than half as good. Just 9 per cent of the children on free school meals in the UK will reach that top fifth.

This is an issue that we have been trying to solve for a long time and, in the sphere of education, proposed solutions have generally revolved around one of two key ideas: improving teaching quality or throwing money at the problem.

Over the past 20 years, the government has overhauled exams and curricula; it has tried to “professionalise” teaching and to transform teacher education. It has introduced academisation and pumped funding into schools via a system of Opportunity Areas (12 social mobility “cold spots”, selected for extra support via locally led partnerships, that link all levels of the education system) and now continues to push to “level up” the most deprived areas of the UK.

But what if changing how we teach or increasing funding aren’t the best answers after all? In my book Fractured: Why our societies are coming apart and how we put them back together, I argue that there is another issue we need to address: the segregation that exists in our schools.

What do I mean by that? To illustrate, we have to go back to a time and place when the desegregation of education was high on the national agenda - not in the UK, but in the US.

In 1965, esteemed sociologist James Coleman left his academic life at Johns Hopkins University behind, checked into a Washington DC motel and closed the door to the outside world. Associate professor Coleman was a man in a hurry. His mission was to change the debate on education in America and to do so quickly.

The previous year, the government had passed the Civil Rights Act, which ended segregation in public places, including schools. The law also demanded that a report be carried out into whether black students were getting a fair deal. The question was this: were the Southern states giving schools that taught white pupils more money than those teaching black pupils?

The job of writing this report had fallen to Coleman. He had to present it to President Lyndon Johnson and the Democratic Congress within two years. By the time he checked into the motel in DC, he had just three months left.

Coleman had not wasted the previous 21 months. With a team of committed students, he had already conducted the largest survey of education the US had ever seen. A less ambitious soul would have kept it simple, producing a factual, short report on how money was allocated to different schools. A report like this would have done the job, showing that schools with mostly white pupils were indeed getting more money than schools with mostly black pupils.

Understanding the ‘why?’

But for Coleman, this was not enough. He wanted to know more than just how much money was going into schools. He wanted to know about the results coming out. His report would tell the US whether its white children got a better education than its black children - and, if they did, why.

Yet, to understand the “why”, Coleman needed data on everything: family stability, quality of teaching, size of classes, the ethnic make-up of every school.

It is hard to overstate what a huge task this was. Data of this type had never been collected at a national level. There were no records of school expenditure and no standardised tests.

Analysing the data was no simpler. There was no established way to separate the countless variables that Coleman had insisted on collecting. Whole new statistical methods had to be created.

Throughout this lengthy process, Coleman knew what he expected to find. With the Southern states dragging their feet on desegregation, he believed his report would show that black children had poorer facilities, larger classes and less adequate teachers, and - critically - that this lack of resources led to worse results.

Eventually, the analysis was done. At first, it looked like Coleman’s instincts were right. Majority-black schools were getting less money. Black children were doing less well. But - to his immense surprise - the lack of money did not explain the poor results.

There were plenty of schools with lots of money that were doing badly and plenty of schools with very little money that were doing well. The careful, precise analysis that Coleman had insisted on revealed the truth: the reason black children were doing badly wasn’t down to money, teaching or facilities. It was down to the other kids in the class.

What Coleman found was that poor children did badly if the other children in their class were also poor. It didn’t matter whether they were black or white. A poor child in a class of other poor children did badly, while a poor child in a class of well-off children did well.

As Coleman put it in the report he delivered to the president, whether a child succeeded was a “function more of the characteristics of his classmates than of those of the teacher”. The priority, his report insisted, must be to ensure that the country had schools “where children of all different social classes intermingled”.

The president was not happy. His administration was ready to deliver increased funding to disadvantaged schools. Coleman’s report was meant to provide the justification for this. Instead, it was telling them that they were solving the wrong problem.

Their response? They did their best to ignore it.

Half a century later, Coleman’s findings have stood the test of time. Study after study has come to the same conclusion: if we want a fairer society, and better education for all, pumping money into schools in deprived areas isn’t going to solve the problem. Instead, we need to educate poorer and richer children together.

No study in this area was more thorough than one that began in 2012. Four economists - led by Harvard-based Raj Chetty - committed two years of their lives to gathering together the tax record of every single American born between 1980 and 1982, and their parents. They compared the two in a bid to identify the silver bullet that would fix social mobility, considering everything from university fees to employment rates, levels of redistribution to the amount of local investment.

What they found was that none of these factors had as much impact as bringing people from different income-brackets together.

What about school funding? Yep, you guessed it. Mixing poor and rich children together mattered more.

This shouldn’t surprise us. Most of us know how much networks and connections matter. We know it so well that we have a phrase to sum it up: “It’s not just what you know but who you know.” Getting on in life isn’t just about learning at school and parental support. It’s also about networks and connections.

Who you know defines what you think is possible. I will always remember a child from a not very well-off background who came on a youth programme that I ran. He spent three weeks taking part in a series of challenges with children from all backgrounds, including with children from wealthier homes than his.

At the end of the three weeks, I asked him what difference it had made. He told me that he now planned to go to university when he had never imagined doing so before. When I asked him what had changed his view, he told me that he had made friends with a boy who had always assumed he would go to university. “The thing is, Jon, he’s stupid. So I thought, if he thinks he can go to university, then why can’t I?”

This shows that having friends with high aspirations (even if they are not entirely deserved!) rubs off. It helps you to aim that bit higher and work to get there.

Word of mouth

But it’s not just about aspirations. Many people hear about jobs through word of mouth. If you don’t know anyone who does a professional, well-paid job, you are less likely to ever hear about these options, ever know what is required to get there, or ever get called to an interview, never mind actually being offered the job.

Evidence shows that a young person who meets employer contacts through activities at school such as careers talks or work experience is five times less likely to go on to be NEET (not in education, employment or training) and will earn, on average, 16 per cent more than those who don’t.

Consider a friend of mine, Tolu Olagunju. Tolu was seven years old when his family left Nigeria for the UK. His parents went to work in the NHS and Tolu went to school. He worked hard, got good grades and became the first in his family to go to university. His parents were rightly proud of him.

But there was a problem. To complete his business degree, Tolu had to work for a year in the private sector.

“I was stuck,” he says. “Other students seemed to know people who could open doors. Not me. Where I’m from, people just don’t do these sorts of jobs. I applied for 65 jobs and got 65 rejections. I was going to fail my course.”

Desperate for help, Tolu signed up to a mentoring programme recommended by a friend, run by an organisation called Psalt.

“I got introduced to people running businesses. I realised they were just normal people. It was a huge boost to my confidence. They were prepared to give me a good reference, too,” he explains.

A few weeks later, Tolu applied for another job and got it.

Tolu’s experience is far from unique. Today, Britons of black African origin are more likely to achieve a grade 5 or above in GCSE English and maths than white Britons. And yet they remain more likely to be unemployed. Why is this? Part of the problem is prejudice but another part of the problem is a lack of networks.

Richer children grow up seeing a carousel of alternative career futures just by spending time with their aunts and uncles, or by meeting the parents of their school friends. If our schools cluster rich and poor pupils together, then poorer children will come to believe that “people like me” simply do not take on professional roles.

Here’s the problem. Our society has become remarkably good at separating those who are doing well in life from those who are struggling. No groups in the UK are as geographically and socially divided as the rich and the rest. Within London alone, according to the Institute for Fiscal Studies, median full-time earnings are 53 per cent above the UK average in the borough of Kensington and Chelsea, in the west of the city, and 3 per cent below it in the borough of Barking and Dagenham, in the east.

Our schools have become one of the few places where we might expect to mix with people from across the local community. But the reality is that rich and poor children have become sorted into separate schools. Half of all the children on free school meals attend just one fifth of our schools.

But what can we do about this? We might take a lead from a city where schools are generally underfunded but where children who are poor and rich are educated together. While the schools may be low in financial capital, they are high in social capital.

This “utopia” of social mobility is Salt Lake City in the US state of Utah, which is home to the Mormon Church. Of the people living in Salt Lake, around 49 per cent are Mormons. Every Sunday they go to church.

What is unusual about Mormons is that they aren’t meant to choose which church to attend. They must go each week to the nearest church to their home. That means that every Sunday, a large proportion of Salt Lakers are mixing with and meeting people who live in their local neighbourhood - whether they are rich, poor or somewhere in the middle.

When Bloomberg journalist Megan McArdle travelled to Salt Lake City to understand this social mobility miracle better, she visited a local economics professor. When she asked him to explore why poor children did so well in the city, he pointed to his church’s recent decision to expand its boundaries to include a nearby trailer park.

Through the schools and their churches, Salt Lake City is giving its children something they really need: the connections to get ahead. The result is a level of social mobility that countries across the West are investing millions to reach and still falling short of.

So, how does this help us here in the UK? We clearly aren’t about to all become Mormons. How, though, could we make our schools more mixed?

For some, the answer is obvious: we should ban private schools and close grammar schools. And yet, only around 7 per cent of our children go to private schools and there are only 163 grammar schools left. This argument is therefore in danger of missing a much bigger opportunity.

Ten years ago, the government changed the law on school admissions. It made it legal for every state school in England to reserve places for children who can’t afford to live in the catchment area.

Doing this is not difficult. Every school, by law, is required to have an admissions policy. It must lay out who gets prioritised if the places are oversubscribed. Most schools take the same approach here: children in care come first, then siblings, then whoever lives nearest.

The problem is that parents with money will, understandably, pay to live near the best school. The result is that house prices rise until only people with money can afford to live in the catchment.

Again, changing this is easy. Schools would simply need to add this line to their admissions policy: “We will reserve 20 per cent of our places for children who apply who are on free school meals.”

That’s it. If every school did this, research suggests that it would nudge us towards the fairer society many of us claim to want.

Does this mean that schools no longer need to strive to provide the best quality teaching and learning that they can? Not at all. Does it mean that governments no longer need to fund schools in the most deprived areas properly? Definitely not.

But it does mean that we cannot expect to fix the inequality that exists in our education system through these measures alone. Rather than blaming the issue on teachers or on school leaders, or even on a lack of money, it’s time we started looking at the other people in the classroom - the mix of pupils.

Jon Yates is executive director of the Youth Endowment Fund, and a former Department for Education policy special adviser

This article originally appeared in the 30 July 2021 issue under the headline “Separation anxiety”