There is also growing evidence that the age at which the young start to experiment has dropped in the last few years from 16 to about 14, though the bulk of drug education is still aimed at older children. Drug workers are also finding a significant number of children aged 10 and 11 are abusing substances such as solvents. A child of seven was the youngest to have been counselled for drug abuse at a project in London.
The largest national survey of drug use among the young reveals that the number of users has doubled every two years. Another study in the north-west of England shows that about half have taken drugs by the age of 16.
One of the most distinctive changes is the widespread use of 'soft drugs' among young people and the acceptance that they are part of their lifestyle and recreation, rather than something dangerous and difficult to obtain.
Cannabis is by far the most popular drug. It has become so commonplace in some regions that it is considered the 'norm' for teenagers to smoke it and a recent study found that it was so freely available in some areas that youngsters did not realise it was illegal.
Children often experiment with solvents, such as glue, Tipp-Ex, hairspray, air fresheners, and lighter fuel, before moving on to other drugs.
LSD is growing in popularity, with cards impregnated with the drug in the shape of bright designs selling for pounds 2. The low cost of the drug and a decline in the quality of ecstasy has boosted its appeal.
Other drugs, such as the sleeping pill temazepam, are also widely used by the young, but it is the diversity and availability of illegal substances that is distinctive about the young generation.
The use of heroin, cocaine and crack still remains rare among young people. They are perceived as 'hard' drugs that are used by addicts, rather than by people looking for a 'good time'.
A survey of 752 pupils at schools in 1992 in Greater Manchester and Merseyside found that 47 per cent had taken drugs by the age of 16; 41 per cent had tried cannabis; 25 per cent LSD; 22 per cent amyl nitrite - a type of stimulant; 15 per cent amphetamine sulphate; 13 per cent solvents; 12 per cent magic mushrooms; 7 per cent ecstasy; while only a few had tried cocaine and heroin. The survey showed 71 per cent had been in situations where drugs were offered.
Further evidence comes from a health study of 25,000 children, carried out by Exeter University. In 1989, 11 per cent of boys and 9 per cent of girls had tried drugs in the 15-16 age group, while in 1991 the figure had risen to 23 per cent of boys and 21 per cent of girls.
Six per cent of pupils aged 12-13 had tried illegal drugs or solvents, rising to 11 per cent at age 13-14, and 19 per cent at 14-15.
Ian Wardle of Lifeline, the drugs information service in the North-west of England, said: 'The growth in the 14- and 15-year-old age group has happened over the last few years. Until recently we thought we were dealing with a small minority, now clearly we are talking about a very significant minority that in some areas is more than 50 per cent of the teenage population.'
Most teenagers get their drugs from friends, contacts made at school and in their community, and older brothers and sisters, who usually obtain them from small-time dealer-users. The growth in the dance and club scene has also brought many drugs, particularly ecstasy and LSD, within the reach of young people.
There is also growing evidence that youngsters in rural areas are finding it increasingly easy to obtain drugs from dealers. They are likely to use solvents, cannabis and magic mushrooms.
The low cost of many drugs is another reason for their growing popularity. The young can get high on illegal substances for less than the cost of a pint of lager. Studies in the North-east have found that many teenage drug users now regard drinkers as 'beer monsters' rather than role models.
Drugs have become an accepted part of many teenagers' lives. One drugs worker said: 'Youngsters are being offered drugs on the street, in trains, buses, the metro - everywhere. Parents and teachers are oblivious to what is going on.
'Drug use is no longer abnormal behaviour, it has become part of society and is becoming accepted as the normal behaviour among youngsters.'
Willie McBride, co-ordinator of Crew 2000, a drugs project in Edinburgh, said: 'Drug use for hundreds of thousands of young people has just become part and parcel of their recreation and fun.'