A Sydney headmaster has made headlines for telling parents to “chill” in a recent newsletter and says he has seen a considerable rise in “parental anxiety”.

Dr John Collier, head of St Andrew’s Cathedral School, believes a minority of parents were behaving badly and making “extravagant demands” of teachers.

“I am having to interact with too many parents who have verbally abused, physically threatened or shouted at a staff member,” he wrote in the newsletter.

On 3AW Mornings, Dr Collier explained while most parents he dealt with were delightful, the level of anxiety and aggression is increasing in a small group of parents.

“I do need to protect staff so that they can do their job and teach without being over stressed about dealings with a small minority of parents,” he told Tony Jones.

He said the issues arose from small matters which in “themselves are not worthy of this kind of anxiety and outrage”.

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