Teachers are now working in a CCTV environment
Many teachers say they are concerned about "hidden" surveillance cameras located in their schools.
A snapshot survey of 249 primary and secondary school teachers suggested 84.6% had CCTV in their school.
The research, conducted by the Association of Teachers and Lecturers (ATL), also suggested more than half - 52.9% - said it made them feel safer.
But 23.4% were concerned there may be hidden cameras whose existence was kept from both staff and pupils.
Tonia Matthews, a teacher at Trinity secondary school in Newbury, Berkshire, said: "Students feel secure to know if there has been an incident, i.e. bullying.
"We can then go back and look what happened."
Although 97.6% of teachers said CCTV was primarily used for security purposes, 49.5% said it was used for monitoring pupil behaviour.
Some 16% said it was used for controlling student behaviour, while 10.4% said CCTV was used to control truancy and 72.6% said it was used to monitor and control vandalism.
The majority of those questioned - 76.7% - said surveillance cameras were positioned at the entrance to their school, and almost 10% said they had cameras in their school's toilets.
More than 7% said there were cameras in their classrooms and more than 15% said they had more than 20 cameras in their school.
Dr Mary Bousted, general secretary of ATL, said: "No-one really knows enough about the use of CCTV in schools - it's a very new issue.
"We have set up a working group to look into the use of CCTV and produce ATL guidelines on best practice for schools and colleges throughout the UK.
"Certainly we would want staff to be involved in decisions about the use of CCTV in schools, and strict safeguards for its use.
"Although surveillance in schools can have some positive outcomes, such as discouraging vandalism and violence, we think there are some instances where it should be strictly controlled."