Fifteen-year-old Sam no longer bothers to look up anything rude on the internet. “I’ve got bigger things on my mind,” he says. “Like girls. You don’t look at porn at my age. That’s what you do when you are 12. Every kid in year seven is doing it. That’s when you hit puberty, when you are little and horny.”

Sam is not easily shocked. “You have to see porn one day. It’s a fact of life.

People like sex. It’s what they do. I don’t need to look at porn, but I might have a sneaky peek if I’m in the mood.” His friend Ben, also 15, is equally cool: “It’s only porn. It is nothing special.”

Such attitudes might come as a bit of a shock to a grown-up, but according to a recent survey by the London School of Economics, UK Children Go Online (UKCGO), they are not so wide of the mark. More than half the 9- to 19-year-olds who go online have seen pornography, and a quarter have received pornographic mail, with one in 10 being sent it by someone they know. The survey also found that half of those who have run into online porn are not bothered by it. All this, however, is news to their parents. Only one in six parents had any idea that their children had seen such images at all.

My own straw poll of teenagers confirms the findings. “Yes, I did look at that sort of thing, but once you’ve discovered it, you lose interest, if you know what I mean,” says Richard Browne, a 19-year-old student. “My parents wouldn’t have had any idea, though. They wouldn’t know how to look on the computer at the history of what sites I’d visited.”

Richard’s parents are not the only ones. “The gap between what children are actually doing and what parents think they are doing is the most alarming issue raised by the UKCGO study,” says John Carr, internet adviser to the children’s charity NCH. “Parents are always going to be the first and best line of defence, and the most effective means of support for children who get into difficulties. For them to do that properly and adequately, they need to have an understanding of the internet.” Too many don’t have a clue.

In Europe, 13m children regularly log on, and nearly all Britain’s 9- to 19-year-olds consider themselves web-savvy. The media-rich bedroom is becoming a personal fiefdom from which parents are in danger of being excluded. The market researcher Mintel reports that four-fifths of children aged between 11 and 14 have a television, nearly two-thirds have a video recorder or DVD player and two-thirds have a games console. The vast majority have a mobile phone and a computer at home.

Meanwhile, many of their parents live in the dark ages when it comes to technology. They might just about have grasped the rudiments of e-mail, but they haven’t a clue about the new media. The UKCGO report finds only one child in 14 describing themselves as beginners on the internet, while a quarter of parents are still grappling with the basics. Children consider themselves far more advanced as surfers of the internet than parents. That is changing the dynamic in families, says Sonia Livingstone, co-author of the report.

For example, in Dudley, in the West Midlands, children are being given handheld computers for education and entertainment — on the condition that they teach their parents how to use them as well. The young are not only setting the pace, they are dragging the adults with them into the future.

“I definitely know more about the internet than my parents,” says Richard Browne, who has been online for four years. “They’ve occasionally asked me if what I was doing was okay, and they were concerned, but they didn’t really know what I was up to. They had to take my word for it.”

The dangers of the internet have always centred on three main areas: contact — paedophiles being able to reach children; content — sexually explicit material, extremely violent images or hate sites; and commerce — children getting themselves, or their parents, into financial commitments they cannot afford. Concern over the last is growing, because there is hardly a single online company that follows official guidelines about surfers aged under 12.

Content and contact, however, remain the key worries. Some safety messages are getting through. “You should never give out your personal details,” 15-year-old Sam says. “People who do are idiots. I reckon they deserve to be abducted for being so stupid.” Many of his peers are not so wise. Nearly half of 9- to 19-year-olds who go online say they have given out personal information, according to the UKCGO study. Only one parent in 20 knew this.

Parents can simply put their foot down. “I’ve never been allowed to use chat rooms,” says Katie McQuaid, a 19-year-old student. “Nor has my little sister.” Richard Browne, whose hobby is designing websites, wasn’t allowed to have his own until he was 18 and had his own Switch card to pay for it. “My parents thought I was too young to have a commitment of £5 coming out of my own account every month for the web hosting. But then it took them a while to let me have a contract mobile phone. My parents are very innocent. They are not overly strict, but they like to keep an eye on what I’m doing.”

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