Police stopped three youngsters in the Downs View area on Saturday after they were spotted acting suspiciously near a marked police car.
As an officer approached the girl and two boys from the area, she could smell cannabis.
Each youngster produced a grinder and a bag of the Class B drug, which the police confiscated.
But the officer, aware of the identity of the youngsters and in possession of their details, decided not to arrest them.
The three will now be re- educated through the Wiltshire Crime initiative, which could take the form of a meeting with drugs workers and the youths’ parents.
They will only have this opportunity once, and should they be caught in possession of drugs again they will be dealt with in the usual manner.