Beijing has a burgeoning international school sector offering many different types of school, but under central government rules, none of them is allowed to accept local students. By contrast, public and private schools serving mainland children can admit some international students provided they meet certain criteria - and more than 75 in the city now do so.

The growth of the alternative track has fuelled a trend among the capital's expatriates to send their children to study alongside local students, in a bid to give them a head start in Putonghua.

British architect Rory McGowan and his Russian wife have enrolled their two children in Fangcaodi Primary School, a Beijing state school teaching the Chinese National Curriculum that has been admitting foreign students for more than 40 years.