It’s a Pygmalion-style experiment: in the music room of Brighton college, 11 bright children from a comprehensive in one of the poorest parts of east London are slugging it out for a free place at this top private school.

Sixteen-year-old Tosin Teriba (“most people call me Tossi”) is telling the interview panel how she recently gave a speech at a memorial service for a friend who “died due to knife crime”. “I said we have to stand away from knife crime and drugs,” she tells the panel solemnly.

Will the teachers watching these teenagers whiz through their three-minute presentations choose Tossi or her schoolmate Horatio, a head boy who likes rapping, debating and can “run 100m in 11.1 seconds”? Will they opt for the bright George Weller, who says some of his current GCSE classmates “just can’t be bothered”, or Anu Adebiyi, whose single mother works as a care assistant?

Then there’s Luke and Natasha and Maureen and Mohammed, William, Nick and Thomas. They all seem desperate to join a school house in the autumn and unpack their suitcases in one of the little boarding rooms of the college, where fees can be £24,000 a year. But there are only two free places on offer. “I want to take them all,” sighs head Richard Cairns.

Whoever is chosen in this new scheme, it’s a decision that will change their lives irrevocably. Every pupil at Brighton college went on to university last year, 16 of them to Oxford or Cambridge. At the 1,500pupil Kingsford community school, in one of the most deprived parts of London, fewer than half the pupils get even five good GCSEs (below the national average). It sends nobody directly to university because it has no sixth form. Two pupils have been murdered in three years — one boy stabbed to death over Christmas.

The Charity Commission made clear on Wednesday that private schools stand to lose up to £88m in tax breaks unless they can show how their charitable status benefits the poor. The result will be schools scrambling to enrol children whose families can’t afford the fees.

Cairns says that his initiative, sponsored by HSBC, has nothing to do with the commission’s announcement on Wednesday and certainly some of the children being interviewed come from decidedly middle-class families. “I’d be doing this anyway,” he insists, but he agrees that private schools will now be looking for ways to boost the number of bursaries they offer.

Of course an experiment that promises so much could also go very wrong. The best-known case of a school giving a helping hand to someone from the other side of the tracks was when a television company paid for south London teenager Ryan Bell to attend Downside, the Roman Catholic boarding school in Somerset, for a Channel 4 documentary.

At first Bell, then 14, prospered, becoming a Latin scholar and excelling on the sports field. But within two years he was out, expelled after a drinking session landed him in hospital. Instead of propelling the council estate child to a life of middle-class prosperity, the project may in fact have changed Bell’s life for the worse.

After all, it’s pretty tricky to settle into a boarding school full of privileged children if you are from a different social background, as Anthony Seldon, master of Wellington college, admits. He has agreed to accept children in care at the new state academy he is sponsoring in Wiltshire. However, he has not opened the doors of the elite Wellington college to them.

In Brighton before they pile back into the white school minibus for the drive back to London, some of Kingsford’s pupils admit they were expecting to encounter “stuck up” people. One anticipated bunk beds and dorms. All have thought about how lonely it might be to be away from their families for a week at a time. “You can go back at weekends or phone if you are homesick,” said one.

They tried hard to be loyal to their state school, but glimpses of what these children have to deal with filter out. Some seem to be weighed down with the responsibility of telling their peers to stop messing about, to buckle down and work. Asked what the worst thing she had done recently was by the panel, Tossi said, “I shouted at this young boy. He was always in trouble and fighting. I made him cry. But he has changed now.”

In her interview Maureen says people she knows “are now living up to the bad boy image of the East End”.

Over lunch — asparagus spears wrapped in ham, lamb cutlets, fruit salad — the youngsters are coaxed to relax. Could most pupils from his school make the adjustment to Brighton college, I ask one. “To be blunt, no. They would just get into trouble here,” is his straightforward answer.

By the end of the day the long list of 11 has been whittled down to five. Tossi, George, Horatio, Luke and Anu are still in with a chance. Next week comes the final cut.

“There are so many of us like me who are there who want to realise their potential but can’t,” says Tossi.

“It’s a different world,” says Cairns. And whether the two can be made to mix successfully is a moot question.

Private initiative

Damaged children from broken homes will be offered free boarding at top private schools this autumn. The government’s education adviser, Cyril Taylor, says that if the country’s 600 boarding schools each took five children a year they would deserve their charitable status tax breaks. Last week social workers from 10 councils met with 50 schools to try to match them with children in care.

Other councils such as Kensington and Chelsea in London, where councillor Shireen Ritchie, Guy Ritchie’s stepmother is looking at the scheme, are also considering private boarding.

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