The 24-hour closed circuit systems are being called upon by principals as "third umpires" to settle disputes and solve cases of vandalism and theft.

The hi-tech watchdogs have won the backing of the Victorian Principals' Association, which wants all new schools to get surveillance cameras.

Association president Fred Ackerman said hundreds of Victorian schools now reviewed security footage when problems could not be solved.

"It's a positive step, and a reflection of where we're at in society, as parents and kids want to make sure they feel safe at all times," he said.

"Using camera footage against bullying is a side benefit that ensures kids think 'I'll be more careful about what I do and say'."

Principals said misbehaving children tended to confess when confronted with video footage.

Albion North Primary School's acting principal, Paul Griffin, said being able to review video footage to resolve student fights was an unexpected extra advantage of installing 16 CCTV cameras, worth more than $30,000, last year.

Security cameras were set up in the school after computers were stolen and windows smashed in three break-ins over six months.

Mr Griffin said cameras were not used to spy on students, but films were reviewed to settle incidents to which no child had owned up.