Management at Te Awamutu College will complete an internal investigation before deciding the fate of four students who got involved in a fracas with police.
All four were arrested after the incident on the edge of the school grounds just after 11am yesterday.
Principal Tony Membery has labelled the actions of the group as "hot-headed, impulsive and irrational".
"They will face disciplinary action from the college ... they know they're going to have to face the music over this."
It all began after staff called the police youth aid officer to help out with an "agitated" student who had stormed off.
Two officers arrived and arrested the boy but he managed to get free of their grip.
Senior Sergeant Stephen Ambler, area response manager for Te Awamutu, said the student then jumped over a fence and began kicking a police patrol car. Back-up was called, but before they arrived a large group of other students ganged up on police and became involved in a minor fracas before the situation was brought under control.
Three other students, aged 14 and 15, were subsequently arrested for obstruction and were now being dealt with by Youth Aid.
Mr Ambler said the teens seemed to have a "pack mentality" during the incident.
"There were definitely a lot of youth around and there was a pack mentality in relation to it but our staff dealt with it appropriately and proportionately in relation to the incident they were confronted with."
Mr Amber said the damage caused by the group was relatively minor.
Mr Membery said the three students only escalated the situation by getting involved and "being abusive and trying to prevent him being taken into custody".
"The school are treating this as a serious incident, an isolated incident, of gross misconduct."
Mr Membery said the punishment for students would depend on their level of involvement and "what they had to say for themselves".
"Four kids don't represent 1200 and they got it horribly wrong and they will know they got it wrong in the cold light of day and will be anxious about the outcome."
• Four pupils, aged 14 and 15, arrested
• Patrol car damaged
• Wall of building damaged
• Students hurl abuse at police