Stephanie’s parents have said they have no intention of emigrating from Hong Kong before the handover of the British colony to Chinese rule in 1997. But virtually every day she comes from school with news of another classmate who is leaving. “We must leave soon, mummy,” she urges. “1997 is getting close. ”

Anxiety about the handover is growing among schoolchildren, according to a survey released this month of 12 to 15-year-olds in 37 secondary schools in the colony.

Almost a third (30 per cent) expressed worries about the 1997 handover, according to the Learner-Teachers’ Association, which carried out a similar survey in 1984. In the past decade more than half a million Hong Kong people have emigrated, principally to Canada, Australia, the United States and Singapore.

The association’s survey found that 10 per cent of schoolchildren were puzzled about their parents’ plans for emigration.

Clinical psychologist Joseph Lau, of the Society for Child Health and Development, which held seminars to teach parents how to prepare their children for emigration, said: “Unnecessary anxieties are caused because parents are not frank with their children and do not prepare them for this very stressful experience.

“Children with behavioural problems due to anxiety are on the rise and emigration appears more frequently as a factor,” Mr Lau said.

Anxiety is not merely caused by uncertainty about their own futures but also the loss of friends and high turnover of teaching staff. In the early 1990s research into dramatic rise in suicides among schoolchildren found that the loss of close friends because of emigration had left many children depressed and with no one to turn to to discuss their problems.

According to education department statistics, a third of teachers who left the profession in the last school year emigrated.

The desire to leave before 1997 has also led to an increase in the so-called “parachute kids”, who are sent overseas for their education unaccompanied by their parents, in the expectation that parents will follow later.

Mr Lau, who has carried out studies in the United States, says that “parachute kids”, having to cope without parental support, find adjusting to their new schools and culture and studies in a foreign language highly stressful.

Parents who intend to emigrate put pressure on their children to perform at school so that getting into good schools and universities in Western countries is easier. The demand for English-medium education in Hong Kong has rocketed. Hong Kong’s English Schools Foundation schools, originally set up to provide an education for the children of colonial civil servants, now have up to 80 per cent Chinese children. Many are children of Hong Kong-born parents who returned after obtaining a foreign passport, but many more are from families hoping to emigrate.

In one ESF school less than 60 per cent of the class of nine-year-olds will be returning this September, the highest percentage since 1991 when emigration was at record levels after the June 1989 Tiananmen Square massacre in Beijing, which caused panic applications at foreign consulates.