A school has spent £4,000 installing sensors in its toilets to crack down on pupils vaping.
Baxter College in Kidderminster is one of the first schools in the UK to use the devices, which detect fumes from e-cigarettes and send an alert to management.
The sensors also pick up sound above a certain volume and can detect if the devices have been tampered with.
Staff hope it will deter vaping, which has become popular among teenagers.
Head teacher Matthew Carpenter told the BBC: "When we were doing student surveys a lot of our younger students were saying they didn't like to go into the toilets because students were going in there to vape and it was making them feel uncomfortable.
"Vaping's an issue nationally. I think a lot of schools... are talking about what an issue it is in their toilets. There's a lot of interest.
"[The sensors] aren't cheap, but they make a big difference, so there's a few [head teachers] coming out to see how we've implemented it."
Mr Carpenter said the school had seen a "substantial" difference in the number of times pupils asked to go to the toilet during lessons.
"We log every time a child goes to the toilet and we have seen a decrease... so pupils are more focused on their learning, which is what they're here to do."
'My mates weren't happy'
Mr Carpenter said within days of the sensors being installed some pupils had been caught vaping by the on-call team.
"Children will always push boundaries," he added.
Asked about the reaction, one pupil said: "A lot of my mates weren't happy about it because a lot of them do it."
The Action on Smoking and Health charity estimated that in 2022, for the first time ever, more 11-17-year-olds had tried an e-cigarette (15.7%) than had tried a cigarette (14.4%).
Source: BBC