Parents have ceded control of the digital home to a generation of children who have mastered instant messaging, Palm Pilots and MP3 players.

Ofcom, the communications regulator, has published the results of a survey of the technology used by 5,000 parents and children, the largest “digital audit” yet undertaken.

The results suggest that it is parents who are struggling to monitor the websites, phones, digital television and games consoles that are central to their children’s lives.

Tessa Jowell, the Culture Secretary, asked Ofcom to assess the “media literacy” of Britain’s children. She believes that a child’s ability to evaluate televison programmes critically and understand new technologies “will become as important as maths or science”.

One in five children aged between 12 and 15 has a weblog and a website. One in four uses the internet to buy and sell goods through auction sites such as eBay and QXL.

One in eight children aged 8-11 and one in five aged 12-15 owns an MP3 player. Nearly half of all children see nothing wrong with the illegal downloading of music and films. A small number of children aged 8-11 (4 per cent) use Palm Pilots or personal digital assistants to manage their time, according to the survey.

Even relationships are being affected. Only 41 per cent of children would end a friendship or relationship face to face. One in five would use a text message or, for the briefest of dismissals, an instant messaging service.

More boys use the game consoles that are found in half of households with children, while girls spend more money on mobile phone services. More than 40 per cent of children aged 12-15 pay their own mobile telephone bill, at an average cost of £10.50 a month.

Television is still more popular than the internet, with the average child watching 14 hours a week. But classes in how to watch television may benefit a generation brought up on Big Brother. One third of those aged 12-15 believed that “reality TV” programmes presented the truth all or most of the time. Half of all children questioned had responded to an interactive television programme either by “red-button” voting, e-mail or sending a text message. Girls aged 12-15 were more likely to respond (69 per cent) than boys (44 per cent).

Monitoring usage of digital devices was a challenge for the parents interviewed, who agreed that their child knew more about the internet than they did. About half of households with internet access have no software to limit children’s access to certain websites. More than 70 per cent of children aged 12-15 use the internet at home unsupervised.

Seven out of ten parents with cable or satellite television have set no controls to restrict their children’s access.

The survey suggested a regional digital divide. Children in Wales and Northern Ireland were less likely to own an MP3 player, create their own websites or use instant messaging than English children.

Most children said that they trusted the information provided on websites, although children from ethnic minority groups who took part in the survey were more sceptical.

Ministers will use the data to propose changes to the national curriculum. More attention will be given to teaching responsible use of the internet. Ms Jowell wants children to understand the methods used to sell products, and the messages that are contained in television programmes.

Tim Suter, of Ofcom, said: “The report provides insights into a generation whose media experiences are markedly different from their parents.”

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