Secondary school principals are unsure where to stand on students vaping in school.

A principal at one of New Zealand's leading High Schools is concerned vaping in school has become an epidemic.

At least 12 Auckland Grammar students have been stood down for vaping in the toilets in the last few weeks.

New Zealand Principal's Federation President Whetu Cormick told Mike Hosking not much is known about the effects of vaping yet.

He says no school would allow cigarettes - but for now it's up to Principals what their stance on vaping is for now.

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