Schoolchildren on Teesside are being encouraged to take their mobile phones into the classroom on Wednesday as part of an anti-theft drive.
Police will visit Ormesby Secondary School in Middlesbrough to encourage youngsters to register on the national Mobile Equipment Database.
This means if they are stolen ownership can be traced and the phones returned to their rightful owner.
Letters have been sent to parents asking for their consent.
Sgt Glynn Bass of the Crime Reduction Unit said: "Last year there was a total of 537 mobile phones stolen in the Cleveland force area - this system will ensure that any mobile phones that end up in the hands of a criminal can be traced back to the rightful owner.
"This is the first of a rolling programme of visits to schools in the area in the hope that we can reduce crime."