Nearly one in five teachers are aware of students using cannabis within school, a survey suggests.

The NASUWT teaching union, which carried out the survey of nearly 4,000 members, warns that drug and alcohol use by students is contributing to disruptive behaviour.

Of the teachers responding to the survey, 13 per cent said they were aware of students using nicotine pouches, also called “snus”, within school, 9 per cent said the same for spice, and 7 per cent said students were drinking alcohol.

In addition, 5 per cent of teachers said they were aware of students using other drugs in school, such as cocaine and ketamine. Similar proportions said they were aware of students gambling or using nitrous oxide at school.

Students smoking cannabis and drinking

A much higher proportion of teachers said they were aware of students using these substances outside of school.

More than half of teachers (57 per cent) said this for cannabis and alcohol (55 per cent), 30 per cent for nicotine or snus, 25 per cent for nitrous oxide and 16 per cent for other drugs.

Nearly three-quarters of teachers said they were aware of students consuming energy drinks at school.

Matt Wrack, acting general secretary of the NASUWT, said substance use is “contributing to the rise we are seeing in disruptive, violent and abusive behaviour in schools”.

“NASUWT teachers tell us that along with increased tiredness and lack of focus and interest in learning, they are causing irritability, mood swings and erratic behaviour among the pupils they teach,” he added.

The union is calling for partnerships between schools, health services, police and youth justice services to tackle drug and alcohol use.

The NASUWT has also reiterated its call for every school to have access to a counsellor, and for the government to ban drinks with more than 150mg of caffeine for under-16s.

Gambling ‘concern’

One teacher responding to the survey said students “tend to present as disengaged from school once they become habitual or heavy users of cannabis or alcohol.”

Another said gambling was a “very real concern”, with students coming into school half asleep after gambling online all night.

Teachers were questioned about students’ use of substances in January 2025 as part of the NASUWT’s survey on behaviour in schools. Responses were received from 3,907 NASUWT members.

A Department for Education spokesperson said the government backs teachers to take action against illegal drugs, including suspensions, permanent exclusions or reporting to the police.

The DfE added that it is tackling poor behaviour through its new attendance and behaviour hubs and expanding access to mental health support in schools.

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