And since 2004, the number of Russian students at British "public" (ie private) schools has more than tripled, according to the Independent Schools Council.
"There is nowhere else that really does education like this system. These schools look more like Harvard or Yale," William Petty, co-director at Bonas Macfarlane, the high-end tutoring firm which gets around 60-70 percent of its consultancy business from Russians, told CNBC.
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One of the early examples of the modern breed of U.K. educated Russian elite is Kirill Makharinsky, son of oil and gas investor Leonid, who went to Eton, got a first at Oxford, and is now an internet entrepreneur who founded Russian travel site ostrovok.ru.
For rich Russians, part of the attraction of these schools is their difference from their own country, with separation of the sexes and full time boarding.
The English countryside, where most of the more prestigious boarding schools are located, is seen as a safe place for those who might be vulnerable to kidnapping. The education itself is viewed as the best in the world – and the network built by being at school with future Prime Ministers and captains of industry can be second to none.
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Fictional representations from Hogwarts to Malory Towers have helped fix the British boarding school as a symbol of aspiration. The U.K. has a lucrative line in education exports, which have grown from £14.1 billion in 2008/09 to £17.5 billion in 2011 according to UK Trade & Investment.
And the contributions to the U.K.'s economy don't stop with fees of up to £40,000 each year.
"The children will buy uniforms, and burgers when they go into town, and the parents will come and stay in a good hotel and spend money on flights," Hilary Moriarty, director of the Boarding Schools Association, told CNBC.
Headmasters around the U.K. are keeping a close eye on enrolment figures for this year, in case the sanctions imposed on Russia over the annexation of Crimea have any effect. The main side-effect so far has been an uptick in wealthy Ukrainians trying to get their children into British schools, according to Petty.
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