"Schools take the most basic of human desires and ignore it in the hope it will go away," explains 18-year-old Jay Burnett, summing up his experience of sex education.
"I received about three hours of sex education and none of it was useful."
Andrew Maher, 11, says that when children arrive in school, they already understand that "sex is when a man and a woman love each other and they want to have babies". However, as Ciara Folan points out, teachers can wait until year six to raise the issue, and, even then, "they don't tell you about humans, only about the life cycle of frogs".
When human reproduction is taught, it is often too late for many girls who are already facing the realities of puberty.
"I haven't had my periods yet, but some girls in my class have," says Ana Mackay-Beasley, 10. "We talk about it so I know what I should do when I have a period."
Girls were left to piece together information for themselves.
Kierra Box, 12, agrees that current approaches are failing pupils. "In biology, sex is really clinical, it's just diagrams," she says. "Teachers say we'll talk about feelings, but they give up."
Stuart Fletcher, 15, believes sex education is treated as an unwelcome diversion. "You don't get to understand it fully because teachers cover it in three lessons and move on. We ask questions but the teachers say `go and ask your dad'."
Senab Adekunle, 15, was doubtful that even the more confident teachers knew what young adults were really concerned about.
"It's basically, should I have sex? If I do have sex, how do I have it? How should I get my contraception? If I don't have sex, is he going to dump me? Is he still going to love me? That's what we need to know," she says, adding that teenage magazines are streets ahead in matters of education. "An article called `Am I Ready for Sex?' was serious and it made me think about whether giving him my virginity was worth it, and what the consequences might be."
"We didn't get beyond how to make a baby because pupils came from a mainly Muslim background. Teachers thought that if parents found out sex had been discussed, they might get into trouble," says Delwar Hussain, 18. "Sex is a big taboo in most Muslim homes."
For Lizzie, getting the facts straight is more important than avoiding the moral debate they raise: "I'm Catholic, but I believe that contraception should be taught anyway. It's like you can't have sex unless you're going to have kids, which just isn't the case these days."
"How are my straight parents supposed to teach me about homosexual relationships?" asks Jay Burnett, 18. "My teacher wasn't willing to discuss homosexuality. Instead, he encouraged everyone to talk to me."
Stuart, who attends a single sex school, highlights the difficulties faced by boys who, unlike girls, rarely feel able to talk to one another. "Pupils should have the option to go and talk to teachers outside school. If you want to discuss things like homosexuality it's better to do it in private rather than in front of your class," he says.
"Teachers need to concentrate on the cultural and the psychological side of things, the commitments and the one night stands, and to be able to explore myths and destroy them," concludes Jay.
Julia Press, 17, argues that: "Sex education should be a greater part of the national curriculum.
"This way, everything you learn about - the biology part, the emotional part, the homosexual part - would start with the basics in primary school and by the time you reach 15, you would know everything."
Children's Express is a programme of learning through journalism for children aged eight to 18.Reuse content