Sex remains an awkward subject for most local parents and schools. Many families avoid discussion altogether and leave to teachers the responsibility of inculcating youngsters with a healthy attitude to sex. All too often schools simply advocate abstinence or adopt a clinical approach that leaves teenagers none the wiser.

In recent years, however, a handful of colleges and community groups have been chipping away at hidebound ways. Spurred by evolving social mores and the reach of new media, they are engaging students with open and creative ways to learn about intimacy, self-respect and responsibility.

At Kau Yan College in Tai Po, guidance teacher Cheng Ying-ha and her colleagues are sweeping aside old taboos.

'In the past, we would not demonstrate use of condoms, for instance. But such conservative ways will backfire nowadays given more liberal social attitudes and mass media with a penchant for salacious reporting. If students don't have access to sex information at school, they just go to the net, which is filled with spurious content.'

Subjects that teachers used to avoid, such as masturbation and oral sex, are on the agenda, Cheng says. Kau Yan collaborates with organisations such as the End Child Sex Abuse Foundation to provide pupils with appropriate knowledge; the Yang Memorial Methodist Social Service helps explain condom use to its second formers and, despite the occasional red faces, the school's science teachers give demonstrations to senior secondary students using an organ model.

'Some teachers feel embarrassed but they think the demonstration is necessary because there's too much misinformation about contraception on the internet,' Cheng says. 'We want students to be well informed in such matters.'

It certainly grabs attention in class. 'Students are mesmerised,' she says.

Lessons built around topical issues also keep them relevant for youngsters. Thirteen-year-old Koo Ho-ching says she gained some insight from a workshop last month that focused on compensated dating (when girls become paid companions to earn easy money, often to buy luxury items). She saw the practice as not very different from prostitution and wondered why girls made such unwise choices. The workshop helped explain how things might slide.

'They go for paid dates with no sex at the beginning, but as time passes, moral boundaries become blurred and hand-holding, kissing and caressing evolve into sex.'

Organisations like Yang Methodist train teachers to follow up with more in-depth discussions; for example, on how compensated dating might affect the girls' emotional well-being.

At the same time, they enlist students to help spread what they learn by organising plays, talks and other activities at school; Ho-ching is among the ambassadors.

'Students are more at ease talking to each other about sexual matters. Many parents are reluctant to discuss [such matters] with their children, and may be too shy to ask teachers,' Cheng says.

The FPA 's Sexuality Education Pioneer Training Programme gives young recruits, usually in groups of eight to 10 students, a crash course before they begin to organise activities, with an education officer visiting regularly to help oversee their work.

'Equipped with the right knowledge about sex, student ambassadors can rectify their friends' misconceptions,' Lee says.

'Our aim is not to preach abstinence. We spell out options available, like abstinence, delayed intercourse or having sex. They have to understand the consequences that come with their choices. We want to help them make informed and responsible choices.'

The intensive training and the extensive resources required means the scheme can only cover a couple of schools every year, Lee says. Launched six years ago, it has reached just 14 of the estimated 400 secondary schools in the city.

But youthful creativity can bring surprising successes. A team of 11 students created a game for smartphones called Happy Egg and Hungry Sperms to teach children how babies are conceived, and it's proving to be a hit.

Although teenage pregnancies have fallen significantly (census figures show 166 births by women under 18 in 2010, compared to 247 a decade ago), welfare groups including Mother's Choice find sexual misconceptions are still widespread among young people.

The prevalence of misinformation isn't helped by gossip rags filled with racy pictures of scantily-clad women and prurient news reports about rape and teenage promiscuity.

Coupled with easy access to pornography online, such sensational portrayals tend to foster casual attitudes towards sex among youths, says Koo Kam-wing, a social worker for the Caritas Project on Prevention and Treatment of Sexual Trauma of Youngsters. 'From my experience counselling young people, many go to bed with people they barely know [after an online encounter]. Some girls use sex to boost their self-image, feeling proud that they can attract the opposite sex. But deep down, they don't know whether they want to have sex [with that person].'

At Baptist Lui Ming Choi Secondary School in Sha Tin, teachers have stepped up sex education initiatives. Besides holding talks in class and at assemblies whenever sensational reports appear, the school has produced its own teaching kit with specific topics for each form.

Chan Wai-yin, who leads the life education team at Lui Ming Choi, says Form One students learn what drives teenage curiosity about sex, how hormones affect reactions and how proper body language can help avoid misunderstanding.

In Form Two, they talk about dating and help students understand why they crave intimacy. Issues about premarital sex and cohabitation are introduced in Form Four and Form Five.

An Education Bureau spokeswoman says senior secondary students now get greater exposure to sex education through subjects under the new curriculum introduced in 2009, including health management and social care. This year, junior secondary students will receive more exposure on topics such as learning to love and attitudes towards sexuality under a new subject called life and society.

The bureau provides guidelines but decisions about sex education are largely left to individual schools, and the breadth and depth of what is taught varies widely.

Students may be turned off by topics like unwanted pregnancies and venereal diseases, but Lee of the FPA says creative use of media such as games and animation can draw their interest.

Caritas' sex education arm recently launched a Facebook project to reach out to young people who now conduct much of their social lives online. Besides posting information on the Facebook page, social workers are in place to answer queries about sex, says Vanessa Chung Ling-wai, leader of its Love and Charity Comprehensive Sex Education Project.

'They are free to ask anything and can be sure their privacy is protected.'

Last year, Caritas also developed a play exploring issues through the tale of a teenage couple. Despite a script featuring explicit dialogue, the play has been staged at about 10 schools.

A performance at Henrietta Secondary School in North Point a couple of months ago captivated the young audience.

Woven between the scenes are question-and-answer sessions in which actors encourage students to talk frankly about sexual matters instead of resorting to euphemisms.

Koo says the play is a departure from the scare tactics that many schools adopted in the past to promote abstinence.

'Some schools still tell tragic stories of unwanted pregnancies and display horrifying images of abortions and venereal diseases to scare teenagers off sex. But such approaches do not promote critical thinking. All the bans on dating and talk about exercising restraint will only further pique their curiosity. Being open with them is the best way to demystify sex.

'We went out of our way to design scenes that would resonate with young people. For instance, a girl uses sex to reconcile with her boyfriend after a heated argument; a boy plays a prank on his female classmate by splicing a nude image with a photo of her face and a male student gets bullied for his effeminate ways. These are all familiar to students. We encourage them to think about what motivates the characters, the fallout from their actions and eventually decide for themselves what they should do if they face similar situations.'

Despite students' overwhelming responses, Koo says they regularly face resistance from principals and teachers who baulk at tackling sensitive topics. 'The play only helps youngsters understand sex matters without any preconceived judgment. Morals should be left to schools to teach according to their religious persuasion.'

At CMA Secondary School in Kowloon, teachers understand the importance of taking a non-judgmental approach to sex education.

Wong Chung-wah, who chairs its health education committee, says students are put off by classes that take a severe stance based on value judgments.

'Young people should be able to decide for themselves and be responsible for their own actions. Instead of forbidding dating, we teach them how to handle romantic relationships. Our teachers have gained the trust of students, who often come to us with queries about romance or sex.'

CMA Secondary also gained useful experience in gearing up for a switch from an all boys to a co-ed college in 2010. The school introduced a scheme for girls in junior forms, dividing them into small groups to learn about sex and relationships.

'Being in the minority surrounded by swarms of boys, they might feel intimidated. We teach them how to get along with the opposite sex and other sexuality issues,' Wong says.

To encourage open discussion, the school has also invited a doctor who hosts a sex education programme on local radio to join its teachers in staging a campus radio show in April.

Lam Min-sze, a Form Two student at CMA Secondary, appreciates the conducive environment for candid discussion at her school.

'My parents never talk about sex with me. Intimate scenes on television make everybody in the family embarrassed,' the 15-year-old says. 'At school, we chat about everything, like premarital sex and teenage pregnancy, in small groups. Such sharing sessions are more interesting than lessons in a classroom.'