Read All About Top British Schools, on the Tube LONDON - Along with the usual flashy campaigns for budget airlines, cosmetics, mobile phone providers and poker Web sites, a sober black-and-white advertisement by some of Britain's most prestigious private secondary schools will greet commuters on the London Underground for the next few weeks. Often pilloried as the preserve of privilege, 23 of the British capital's most expensive schools have collaborated on a campaign for parents whose academic aspirations for their children may exceed their financial grasp. "School fees may not cost as much as you think," the ad reads. If your child can pass our exams, we can help with the fees. The list of institutions offering financial aid includes King's College School, Lady Eleanor Holles, St. Paul's and Westminster - all regular fixtures at or near the top of various secondary school rankings. The program is the brainchild of Martin Stephen, a former "high master" at St. Paul's, where fees are nearly £20,000, or $32,000, a year for day pupils and £29,000 a year for boarders. "I'd been high master at Manchester Grammar , and a lot of the schools up there used to run a joint campaign for the Assisted Places Scheme," he said of a boys" school in England's northwest. Under that arrangement, which was ended by Prime Minister Tony Blair's Labour government in 1997, the government paid the tuition of some students whose families could not afford to pay private school fees. When I came down to London I found a cutthroat competition among schools. There was absolutely no sense of partnership," Mr. Stephen said in an interview in which he described his own efforts at fund-raising and scholarships for poorer students as "frankly, payback." My father, Sir Andrew Stephen, became quite an establishment figure. He was a doctor and the head of the English Football Association, but he came from a very poor Scottish background. So in a sense I owe my start in life to the fact that he had a very good education," he said. Most "public schools," as the British refer to their country's older private secondary schools, have traditionally offered some form of financial aid. Eton - which counts Prince Harry, Prime Minister David Cameron and Sir John Gurdon, who was awarded the 2012 Nobel Prize for medicine, among its alumni, and where fees are currently £32,000 a year - was founded by Henry VI in 1440 as a school for paupers. Nowadays, however, such schools tend to cater mainly to the children of the wealthy. The welcome extended to the brighter children of the poor, though genuine, has long been more discreet. According to Mr. Stephen, the current outreach campaign began several years ago, at first with just a Web site and a handful of newspaper advertisements, written by a St. Paul's parent. Kenneth Durham, head of University College School, who took over as coordinator from Mr. Stephen two years ago, said, "We felt that if we were serious about appealing to people who wouldn't normally think about sending their children to independent schools, then we needed to advertise more widely." Each school pays £5,000 a year to cover the cost of placing the ads. Some of the money also pays for Internet search optimization. The current campaign has already generated more than 40,000 hits on the consortium's Web site . "Since we've been doing it, we've had more applicants for assistance at U.C.S., although I don't know if you can credit the campaign for that," Mr. Durham said. University College School, which charges annual tuition of £16,575, currently gives financial aid to 7 percent of its students. It's a small percentage. But all of our assistance is means-tested," Mr. Durham said. Only 7 percent of British students attend private schools. The fact that a small fraction of a small proportion of students will benefit from the campaign prompted criticism from Melissa Benn, the author of "School Wars: The Battle for Britain's Education" and a prominent advocate for state education. "I see this as just one of multiple moves to bridge the gap from private to state education," she said, pointing to the promotion of free schools, which are state-funded but independent of local government control. "I think this is the wrong approach, because I'm trying to bridge the gap in the other direction, by trying to create a high-quality, high-performing system of comprehensive education like they have in Finland - one of the most successful systems in the world," she said. "This kind of effort creams off the intellectually ambitious and socially ambitious kids and depletes the kind of schools that my daughters go to," Ms. Benn added.