Battersea Park on a Sunday afternoon looks, on the face of it, much as it probably did 20 years ago. Parents stroll, children misbehave, babies cry. But look a little closer and many of the mothers turn out to be dressed in unexpectedly tasteful shades of Euro-beige, while les petits on their scooters, dressed in navy shorts and smocked dresses, answer to Pierre and Marie-Chantal, not William and Georgia.

It’s the same across the river on Bute Street in South Kensington, where the grocer stocks Fraîcheur Active shower gel next to jars of lentilles preparées; where the bookshop advertises Harry Potter et Les Reliques de la Mort; and the clothes and shoe shops have cards in their windows asking for assistants who speak French as well as English. At a café down the road they don’t even bother to pretend: they greet you in French, serve you in French, and most of the tables on the pavement are taken by chic young French couples smoking and eating their salades composées.

There are now so many French people living in London that a state primary school has gone bilingual, and there are so many more in the country as a whole that Nicolas Sarkozy came over to chase votes in the run-up to the French Presidential elections. “France,” one of Mr Sarkozy’s political allies has warned, “is in the process of becoming a country of emigration.”

Wix primary school in Clapham happens to share a building with the prep school for the French Lycée. The geography is no accident: if South Kensington, with its long-established Lycée, is the epicentre of London’s French community, Battersea and Clapham have become its very own suburb, as families wash over the river in search of affordable family houses and good local schools.

But Wix is no ordinary school: it is the first state school to offer a bilingual education. Wix, being a state school, offers it free (including to qualifying French residents); the Lycée, being a private school, charges fees. They used to be entirely separate institutions; now, English and French teachers and pupils collaborate on the bilingual stream, with each school taking in 14 children a year and educating them simultaneously in French and English. It is a godsend for an area full of bilingual families and French emigrés anxious that their children get a head start in the international language of business.

And it’s not just about the language: as the school is not just bilingual but bicultural, its French pupils do the Easter Bonnet Parade and English children promenade at la fête d’été. The corridors of Wix are noisy with children shrieking in two languages and, the day term finished in July, the blackboards bore the date for la rentrée in September as well as the new term.

That there are more than enough French people living in Clapham to support the initiative is revealing: the 14 places each school offers are massively over-subscribed. But while, for the English parents, wanting their child to learn French is largely a romantic gesture, for the French parents, fluency in English is seen as a necessity.

Elise Manechez, from Lille, is a case in point: her five year-old daughter, Clemence, is in the bilingual stream at Wix. “We didn’t want a 100 per cent French education because we want to integrate ourselves with the culture,” she explains. “It’s a very big asset for Clemence to speak English, as most companies are now global.”

A marketing analyst for a mining company, Manechez, 24, moved to the UK in September 2004 with her partner, Jeremy Rossiny, a researcher at Imperial College. Like most of her compatriots, it was because of work: Rossiny found his area of research to be undeveloped and under-financed in France.

“We’re definitely pleased we’re here,” she says. “England’s international. I like the state of mind of Londoners, the jobs... and my daughter is very happy in the bilingual environment. It’s easy to make friends, and I don’t feel like a foreigner. For the first two years I used to say my home was France. Now I think it’s here.”

Her friends are an international bunch, some met at the school gates, others through leisure pursuits. “Most of our friends aren’t French. I like the diversity of people in London, the different communities, sports, nationalities. In France it wouldn’t be that diverse. I like painting and going to art galleries and museums. London’s a good place to be.”

“Clemence has a mixture of English and French friends, most of them bilingual,” she says, “and we are friends with some parents from school. We meet up with the kids at the weekends – sometimes we go to Battersea Park or to a museum. In the spring me, my husband and another couple went to Legoland with our children.”

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