TO FOREIGNERS, few things seem as peculiarly British as the habit of sending young childre

n away from home to school. At first glance, boarding schools are thriving, with almost 70,000 children within their walls .Independent education (both day and boarding) produces better-than-average academic results: they teach only 7% of English pupils but supply 38% of those gaining three or more A grades in the A-level exams takenen age 18.

Yet some boarding schools are struggling. While the demand for private schools has increased over the past 20 years, the number of children at boarding schools has dropped sharply -- from 112, 135 in 1985 to68, 255 in 2005. The decline leveled off four years ago, thanks, say some, to the popularity of the Harry Potter books.

One reason why boarding schools have lost some of their appeal is high fees -- the average is around Pounds 18,830 ($35,470) a year. Lurid stories of children who harm themselves or take drags, far from parental eyes, have not helped. Some schools are in trouble financially: three mergers have taken place this year; one school in Buckinghamshire will close in August; and another, in Sussex, was recently rescued by parents.

Yet Adrian Underwood, national director of the Boarding Schools' Association, describes the future as "rosy". His optimism stems partly from renewed political interest in taking children from foster care and children's homes and sending them to boarding schools instead. Only 6% of those in care in 2004 got five god grades in their GCSE exams (taken at about 16 years of age), compared with 53% of children overall. Boarding schools can offer small classes and good discipline, helping pupils to counter the low expectations that prevent them from achieving all they could.

A working party in the Department for Education and Skills has spent months looking at ways to expand the programme. Pilot projects are due to start in September 2007. Among the 80 or so schools that are interested are Wellington, an independent senior school in Somerset, and the Dragon School, a preparatory school in Oxford. John Walker, speaking for Britain's prep schools (which educate children from ages 7 to 13), says they could take pupils as young as five years old. Local authorities are less enthusiastic. Schools want full responsibility for the children they accept, while councils and social workers want to be able to check up on them. Some think that removing children from any version of parenting could have damaging long-term effects. Holidays are also problematic: the Fostering Network, which represents foster-carets, says that many foster parents are unwilling to have children only for the holidays.

For boarding schools, both those with an idealistic streak and the financially strapped, the appeal of increasing numbers is clear, as long as other parents don' t squawk. They have another reason to be keen. New laws will soon require charities to justify their tax breaks by proving that they benefit society at large. Independent schools, 80% of which have charitable status, reaped pounds 88m in tax rebates in 2004. Accepting a few needy children alight well safeguard that status.

In the opening paragraph, the author introduces his topic by ______.

A．posing a contrast

B．justifying an assumption

C．making a comparison

D．explaining a phenomenon