Rangitoto College is being accused of overreacting to an unsanctioned after-ball party that has prompted the school to cancel next year's balls.
About 150 students, with the approval of some parents, attended a party in an Auckland warehouse after the school's ball in August.
The secondary school, on Auckland's North Shore, called off next year's school balls saying students and parents ignored its warnings not to hold the after-ball function.
Principal David Hodge has described the party as boozy, with an open bar and at best dubious supervision.
Alan Parker, the parent of a Rangitoto student, says he checked the details before allowing his son to go, and there was transport, security and parental supervision.
He says other schools may have had problems with such functions but that is no reason to overreact to a well run event.