They will learn about sex through stories and games - such as blowing condoms up like balloons - rather than sitting through dry lectures, China's official media have reported.

The fresh approach has been introduced as China considers the threat of Aids and HIV.

Surveys have shown that most Shanghai students lack adequate basic knowledge about Aids, and earlier this year Aids prevention became a required course at 15 of the city's colleges and universities.

World health specialists warn that rates of infection could increase massively across China over the next 10 years if people fail to practise safe sex.

Interactive sex education

"Unlike the traditional methods of conducting sex education through lectures and leaflets, the new approach involves greater interaction between students and instructors," the China Daily said.

"An instructor may, for example, encourage shy students to blow up condoms like balloons to get familiar with this common contraceptive device."

Junior medical students will run the programme, which is designed for first year college students in Beijing and Shanghai with "no clear ideas about sex".

The course will be available on eight campuses over the next year, but organisers hope to develop it further with support from western condom producers.

Having fun

A spokesman for the UK's Health Education Authority said the course had a good chance of proving effective, although it would have to form part of a wider programme of sex education.

He said similar courses to reduce the number of teenage pregnancies in the US had been successful.

"Another good thing is that it appears to be peer led," he said.

"It's run by junior medical students and not teachers - they're more likely to make lessons relevant and more fun."

The young are particularly at risk of Aids in China - studies show that 65.5% of the country's HIV carriers are aged between 16 and 29.

Risk of a rise

While Chinese government statistics put the number of mainland HIV virus carriers at 400,000, health specialists say the number of undetected cases is much higher.

It is expected to rise to 10 million by 2010.

The HEA spokesman said that China may well need to undergo a period of "condom normalisation".

"In the UK we have experienced condom normalisation over the past 10 years," he said.