As many as one in four S1 pupils say they care for relatives, with more girls than boys involved in providing key family services. Caring tapers off steadily through secondary school.

The Being Young in Scotland 2005 survey, carried out for YouthLink Scotland and the Scottish Executive, sampled more than 2,000 11-16s. It found that caring is most common where neither parent works or if families live in deprived neighbourhoods.

Their chances of looking after another family member are also increased if they themselves have a long-term disability or illness.

As well as listening to problems and keeping people company, they are likely to do basic chores such as cleaning. Older teenagers juggle a variety of jobs such as weekly shopping, helping with washing or feeding someone and paying bills. But this takes no more than five hours a week.

Very few of them say this has an impact on other things they like doing.

One spin-off is that young carers are more likely to be interested in other forms of volunteering.

Deprivation is an added factor in whether young people take part in sport.

Around half (47 per cent) of 11-16s in deprived communities take part in sport at least once every two weeks, against 67 per cent in the least deprived areas.

Participation falls sharply from S2, especially among girls. Numbers who take part in youth groups and clubs also fall rapidly once pupils reach S2.

One in five 11-12s takes part in uniformed clubs at least once a fortnight, but this slumps to one in 10 by the time they are a year older.