Although there is no statutory requirement to inform the police under such circumstances, Education Secretary Gillian Shephard is instructing schools to do so as part of the Government's new campaign on drug abuse.
In the past, some schools have preferred not to involve the police in some circumstances; others have refused to institute drug policies, fearing that they would be stigmatised by parents and so suffer under the new market forces ruling education.
Stressing that drug use was illegal and should be treated as such, Mrs Shephard said that she was determined to change the climate which had led to concerned schools being stigmatised.
"Schools which failed to deal with the drug problem are failing pupils. If schools have a stigma, it should be these," she said.
In a draft circular, out for consultation until next March, the Department for Education suggests ways in which schools can help safeguard children from taking drugs, stressing that a clear policy must be developed and discussed with parents. Drug Prevention and Schools also lists warning signs of possible drug abuse and action which schools should take under such circumstances.
It stresses that teaching should start with primary school children. Initial teacher training should include pastoral issues connected with juvenile drug-taking, and induction and in-service courses should also be available.
The circular says a teacher who becomes aware of "possible criminal activity" outside school premises would be expected to inform the police, even though there was no statutory duty to do so. This would be in the interests of safeguarding the health and safety of young people in the area and as part of the school's general duty of care towards its pupils.
School staff are legally allowed to take possession of substances believed to be controlled drugs in order to protect pupils from harm and from committing the offence of possession, says the circular, adding that it is open for staff to search a pupil's desk or locker if there is reasonable cause to believe it contains unlawful items. However, staff should not search pupils or attempt to analyse or taste an unidentified substance.
Teachers' own habits may also come under scrutiny. Mrs Shephard is said to be "particularly concerned" at the level of teenage smoking, which she says should be discouraged through school behaviour policies.
"Pupils are likely to be influence by the school environment and teachers' own attitudes and behaviour . . . an increasing number of schools prohibit smoking entirely on school premises or limit it to a designated area for all teachers, non-teaching staff and visitors," says the circular.