One winter’s night a few months ago, an Oxfordshire head was woken by police at his home. A teenage girl pupil was dead - killed by sniffing a solvent. Her three friends had survived.

Three days later, in the midst of handling mass grief and helping with funeral arrangements, the head saw a boy in his office who’d been caught with cannabis; the boy denied it and his father claimed victimisation but police analysis of the substance confirmed the school’s suspicions.

All in a week’s work for a secondary head in 1996. The Oxfordshire head prays it’s never so bad again. But handling drug-related incidents is now part of the job. Young people use drugs - and when they go to school, some of their habits go with them. If they over-step the mark and bring drugs with them, there’s an incident waiting to happen.

It is a year since the Department for Education and Employment issued its guidance on “drug prevention and schools” which advocated a softer approach than automatic expulsion. While few schools have had first-hand tragedies to face like the one in Oxfordshire, many will have had to deal with suspicious substances or rumours of drug abuse.

Sally Perlin (not her real name), deputy head of an inner London comprehensive says her school used to expel - “it used to be nice and clear. Now the Government has gone in for this strange liberalism, and it’s made it much more difficult.”

The guidance contained in Circular 495 recommends support and advice for pupils known to be experimenting with drugs. Heads, it says, must take their own decisions on individual incidents but “the fact that certain behaviour could constitute a violation of the criminal law should not, in itself, be taken as automatically leading to the expulsion of a pupil”.

The Secondary Heads Association backs up the DFEE advice. “Our policy is very much akin to what’s in the circular,” says professional officer Bob Carstairs. “But it is a question of interpretationIin some schools incidents are very unusual, in others it’s almost on a weekly basis.”

The circular was widely welcomed by workers in drug education, as it reflected their own pragmatic approach. The buzz words among drug educators are “harm reduction”. They have moved away from the “say no” approach and now say young people should be taught to assess the relative dangers of different substances, and the least dangerous way to use them - if they must.

While this approach may appeal to teenagers (“they don’t preach to us, because that’s what we really can’t stand,” says 16-year-old Ruth) few parents, heads or governors feel totally at ease with it. Parents - however unrealistically - still want their children to be in a “drug-free zone” and certainly expect schools to be. At the same time schools have reputations which, these days, they are more anxious than ever to keep trouble-free.

“It’s a real problem,” says Sally Perlin. “If there is bother, there’s a terrific fear that the local press will get hold of something. Yet every school is going to have a potential problem, and if they pretend they haven’t, they’re mad.”

The head of Malvern Girls’ College, Dr Anne Lee, recently resigned after saying on the BBC’s current affairs programme, Panorama, that by the time her girls left school “many would have been offered drugs in the holidays”. Unremarkable perhaps, but the governors were said to be unable to stomach her frankness.

Some schools are now taking an upfront position on how they deal with drug incidents rather than ignoring the problem and hoping that it will go away. Keith McClellan is head of a “typical country town comprehensive”, the 900-pupil Cooper School in Bicester. Recently a pupil was found in possession of cannabis at school but charges failed to stick. The need for more effective procedures was clear.

The boy was excluded for a limited period while the police analysed the substance. He mounted a robust defence, claiming to have accidentally picked up the plastic bag containing the dope while making a snowball. “There is great difficulty in proving anything,” says Mr McClellan. “We had to let the boy back in. If I had permanently excluded him, he would have won at appeal.”

As a result, the school has had detailed discussions with the police and established closer co-operation. They now have a bleep link to a police officer so they can call someone in immediately if they have grounds for suspicion. It is not the way the drug educators recommend that incidents are handled, but more schools are believed to be choosing this route, especially in the face of pupil denial. In Greater Manchester the police have instigated a pager system to put schools in touch with a drug co-ordinator when they need instant advice.

Interrogating pupils is notoriously difficult. Most will go to any lengths to deny any involvement in drug abuse. Sally Taylorson, who answers calls to the telephone helpline “Drugs in schools” run by the charity Release says over-enthusiastic interviewing is one of the main causes for concern. “Sometimes the way the interviews are carried out is outrageous. Schools don’t follow set procedures like the police do. One lad was shut in a room without food or water from 9am till 4.30pm. In another case, four teachers were surrounding the child, coaxing and wheedling to get the name of the dealer. ”

The difficulty of proving rumours or incidents is one reason behind the rush in independent schools to introduce drug testing. Every summer Q especially in the lazy days when exams are over - newspaper stories tell of the expulsions of privileged pupils for getting high. In the past two years there have been expulsions from Rugby, Pangbourne and Ampleforth. A number of independent schools now carry out urine tests for drugs.

“The young will lie and lie,” says James Flecker, head of Ardingly College, a Christian foundation co-ed boarding school in Sussex. “Time and time again they get away with it because you can’t break them down.” His policy, made in the light of experience, is to test their word against scientific evidence when possible. “Now if we have reason to feel someone might be taking drugs, we will have them tested.” The advantage for the pupil, says Mr Flecker, is that most pupils who test positive will then be given a second chance.

Keith Dawson, head of the Haberdashers’ Aske’s School in Elstree, chaired a working group for the Head Masters’ Conference which issued guidelines to independent schools last September. “We did not recommend testing,” he says, “although it seems in some circumstances to be a valid way of operating. ”

The legality of testing pupils is described by both the Children’s Legal Centre and Release as a grey area, although they both say it is legal if the child gives consent. The HMC working group guidelines say the independent schools which use the tests should do so with the prior knowledge and agreement of parents.

Schools struggle with these issues while young people’s social lives are becoming more drug-oriented. An ICM poll, published last week, shows that one in three 11 to 15-year-olds has been offered drugs and one in 10 has taken them - of these 80 per cent have taken them more than once. Two per cent have tried drugs aged11, but that rises to 23 per cent at the age of 15.

The authors of a Manchester University study on drug use warn that incidents will become routine in secondary schools - and will involve many pupils who are academically successful. Researchers there found that almost half the 16-year-olds studied had tried cannabis, and that other illicit drugs were increasingly being used.

Professor Howard Parker and his colleagues describe schools behaving “idiosyncratically” in the recent past, with responses to smoking cannabis in school ranging from permanent exclusion plus a police inquiry in one institution, to a letter home and a reprimand in another. They don’t mention the blind eye tactic; in one London school I visited earlier this year, staff ignored the distinct whiff of cannabis on the stairs.

The difficulties in deciding how to respond to an incident are real. “We’ve had one kid off his head now and again,” says a deputy head in a London comprehensive. “Then a member of the public rang to say he was rolling a joint opposite the school. I went over and found him, and he smelled of cannabis and was as high as a kite, but there was no evidence. I wrote to his parents, and they didn’t come in. Then they did and blamed us, saying we didn’t understand West Indian culture.”

Not that drug use is restricted to any particular cultural or racial group. One of the clearest messages from all the research is that all groups of young people are potentially touched by drugs and drug culture.

Claire Burgess (not her real name) is an academic living in a comfortable provincial town with Daisy, her 15-year-old daughter. Claire is a school governor and when her daughter was arrested for possessing cannabis, she was deeply anxious and embarrassed.

“I felt partly inclined to go and speak to the head. I could also have raised the fact that probably 75 per cent of the kids over 15 are regularly smoking cannabis. But it was fairly clear that there was more to be lost by telling them than to be gained. The whole thing was very dishonest. I do try and work with them, but when it came to the big one, I kept quiet.”

Daisy was given a caution and, to this day, her mother doesn’t know whether the school is aware of what happened or not.

Terry Brown, a consultant in health education, believes that schools are excessively fearful of parents’ reactions. “There are a number of stories about individuals who’ve had no other problems except being caught with drugs, ” he says. “Exclusions are not appropriate in these cases, and parents can see that.” Increasingly, he thinks parents are capable of taking the line that “there but for the grace of God go I” - most would not want their own child excluded over experimenting with drugs, and realise that all are vulnerable.

Young people are the first to spot the moral contradictions. Drug education is carried out by people who may still say “just say no” before dashing off to the staffroom for a cigarette and a coffee. Some schools are still permanently excluding pupils for first, or relatively minor, drug offences while beyond the school gates there is a de facto decriminalisation of cannabis reflected by lack of action on the part of the police. Unless there is drug dealing involved, chances are a chair of governors may take a tougher line than a local police sergeant.

“Often the police are quite reluctant to take action,” says Paul Hanlon from the Angel Drug Project in Islington, north London. “Like us they see drugs most days and they don’t particularly want to get a 13 or 14-year-old involved in the criminal justice system.”

The project has trained all Islington’s secondary teachers on how to handle drug-related incidents and the borough has a multi-agency forum bringing schools, police, health workers and others together. All schools have a named link person from the forum to obtain advice.

Terry Brown says adults too need drug education. “People making policy decisions may well be those who know least about the drug situation, and those who are most concerned about external factors such as pupil numbers and PR. But once you do drug awareness with senior management and governors, they often change their views and are willing to set up something that fits with the reality of the lives of young people.”

Still, there is a deep-rooted desire to protect young people from drug use and its occasionally disastrous consequences. There are intractable problems facing staff in some schools in rough, tough and deeply drug-affected areas. “No one’s that worried about a bit of cannabis,” says Sally Perlin. “But it’s the world it brings children into contact with that’s the problem. Suddenly you’ve got these guys in cars with black windows outside school. Then they beat people up if they think they’ve ratted on them. The level of fear of people when they know things is just horrific. But the Government’s bits of paper make out that it’s all about cosy chats with parents.”

Sally Dixon, a former policewoman in the Chapeltown area of Leeds, and now an infant teacher in one of the city’s suburbs, is not optimistic about the adult world’s prospects of turning the drugs tide. She describes children of primary age working as couriers for friends and family, and girls not out of the juniors attending raves. “Some schools are just burying their heads in the sand,” she says. “But this problem creeps out from the city and it affects all of us. If you have children, it affects you.”

* The Release Drugs in Schools Helpline is a confidential service providing information and support to pupils, parents and teachers in dealing with drug-related incidents. It takes calls Monday to Friday from 10am-5pm on 0345 336666.