Kiwi school kids have been physically restrained during school time on 423 occasions in the past three months.

The incidents took place at 186 schools, including 79 specials schools, between August 1 and October 25, the Ministry of Education said in response to an Official Information Act request.

In all instances, the schools reported that the use of physical restraint was necessary "because of a serious and imminent risk of safety to students, staff or others", the ministry's deputy secretary sector enablement and support Katrina Casey said.

Under new rules introduced on August 15, schools must report every instance in which physical restraint is used to the Ministry of Education.

Among the occasions physical restraint was used, 321 instances happened at primary or intermediate schools, while more than half the students involved were on "Incident Behaviour Plans".

Ms Casey said restraint was used in only a small percentage of cases, given there were 800,000 students and more than 2500 schools in New Zealand.

The Education Act defines physical restraint as ""using physical force to prevent, restrict or subdue the movement of a student's body or part of the student's body".

Ms Casey said training for school staff focused on prevention and de-escalation strategies with physical restraint only to be used as a last resort.

"However, there will be times when situations escalate and, on rare occasions, a student may need to be physically restrained to protect themselves and/or others," she said.

This could include when preventing a student from running onto the road or breaking up a fight, Ms Casey said.

- NZN