Traditional British private schools are the new presence in the international school market – brandishing brands sometimes hundreds of years old, rivalling the specialist chains and stand-alone institutions.

The tally of public schools that have set up abroad, or announced plans to do so, includes a mix of boys’ boarding schools such as Harrow and boys’ day schools lsuch as Dulwich College. Even Gordonstoun, a co-educational Scottish school that has taught several members of the British royal family, is considering opening a school in India.

The oddity is that although most of these schools achieve good A-level or International Baccalaureate (IB) results at their original British locations, there are few among the top 20 or so schools with the best results in Britain.

The heads of some of the schools in the highest ranks say they are worried about their reputation if they expand abroad. Martin Stephen, high master of St Paul’s School, calls these overseas offshoots ”a risk to your brand image”.

CASE STUDY

Brighton College, England

Earlier this year, Brighton College announced plans to become the biggest provider of overseas education among the plethora of traditional private schools that have decided to expand overseas in recent years, by setting up a dozen satellites abroad.

Its ambitious move had been long in gestation, like most English independent schools’ forays abroad. But the fact that it finally went ahead in the middle of the credit crunch suggested that global economic difficulties will not stop the sector’s overseas expansion – although it may slow it down.

The school, located on the south coast of England, is in the upper reaches of English private schools academically speaking, rather than the very top echelons. However, it still does well enough to send many pupils on to Oxbridge – a valuable asset in the eyes of foreign partners.

Richard Cairns, headmaster of the school, explained the logic of a big bang rather than piecemeal approach to overseas expansion, saying: “We have never been interested in just one school because we felt that a single satellite school would generate insufficient income... to justify the additional focus and time that such a venture requires.”

This echoes last year’s comments by Mark Pyper, principal of Gordonstoun school in Scotland, who told the FT that discussions with other schools with branches abroad had suggested “they don’t actually bring in great millions”.

Brighton College’s satellites are, in a sense, part of a wider package. They will largely school the children of the local and expatriate middle-class living in new residential developments created by Bloom Properties, the Abu Dhabi company that has chosen the college as its ”educational partner”.

The first satellite, Brighton College Prep School Bloom, will open in September 2011 in the emirate state. The college also plans schools in Oman, Jordan, Romania, Mauritius, Vietnam and India.

Mr Cairns said fees for the satellites, which will all teach GCSEs followed by the International Baccalaureate, will be about £12,000 ($18,800) a year for day pupils and £20,000 for boarding – a few thousand a year lower than the mother school. All will be co-educational, like the mother school.

Bloom Properties has financial backing from Abu Dhabi’s ruling family.

Hani Rayden, head of Bloom Education, the property company’s education arm, said Brighton College was picked because “we were looking for a school that was highly successful academically and with a genuine commitment to developing the whole child”. Brighton College generated great media interest recently by announcing plans to teach etiquette.

The irony is that it is the British private schools’ brand that has impelled them abroad in the first place.

Until the credit crunch slowed down the mania, school heads in Britain had been deluged with letters in recent years from prospective foreign partners – inviting them to set up the franchise operations that are the standard model of British private schools abroad.

Most of the schools that acted on these offers by setting up overseas were not genuinely famous outside Britain – because all but a handful of British institutions are not well-known beyond the UK. But they were benefiting from the strong brand image of the British public school in general.

Harrow, which has set up schools in Bangkok and Beijing, and Gordonstoun are perhaps the only exceptions – largely because of their history of educating royalty. Barnaby Lenon, headmaster of the former, notes in a matter-of-fact manner that Harrow and Eton College (which has not expanded abroad) are “the two most famous schools in the world”.

But it has been difficult for British schools to replicate their exact ambience in countries thousands of miles away.

Most basically, while the original Harrow is a boarding school for boys of 13 and above, the 10-year-old Harrow Bangkok – one of the oldest overseas branches created by a British private school – has almost as many girls as boys, relatively few boarders, and children stretching down to nursery age.

It has also dispensed with some of the famous Harrovian traditions. Pupils do not put on the famous tailcoated uniforms worn on Sundays and special occasions, although Thai parents who want to buy a piece of Harrow history will be relieved to hear that pupils do “sing the traditional Harrow songs”, according to Kevin Riley, current head of The John Lyon School, a London sister school to Harrow, and the Bangkok branch’s forthcoming head from September.

But Mr Riley’s comments also suggest that the Bangkok branch is far from trying as hard as it can to be like the old school. Parents are “buying into” the fact that “it’s Harrow, it’s a world brand”. But he is realistic that a carbon copy is unlikely and that the school will inevitably “develop an identity of its own”.

His chosen trinity of adjectives are ”pleasant, hardworking and cheerful” – very much in keeping with how Thai people like to see themselves. It is a far cry from the buttoned-up image of British boarding school tradition, although some Brits who have been through the boarding experience may be relieved to hear that.

But the most important fact for parents – even those who can say at dinner parties that their child is at an offshoot of one of the most famous schools in the world – is exam results.

Here Harrow Bangkok merits a “not bad” but “could do better”. At the parent Harrow, an impressive 66 per cent of A-levels were A grades last year. At Harrow Bangkok it was 47 per cent, according to the school’s latest figures. This was below the 50.5 per cent average for members of Britain’s Independent Schools Council – although independent experts say this is quite a good result considering the high proportion of pupils whose first language is not English.

But the exacting assessment of Mr Stephen, high master of St Paul’s, suggests that even if a school manages to get its academic results up to the level of the original school, this is not enough. He is sceptical that the “great emphasis on extracurricular activities” that is the hallmark of British private schools can be transferred to daughter academies.

But fans of British private schools’ overseas expansion say this is all the more reason for them to go abroad, since they have more chance of achieving this emphasis on the extramural precisely because they are British. To them, there is some far corner of a foreign field that should, and can, forever be used for cricket practice.

David Turner is the FT’s education correspondent