"This is the biggest fall in youth smoking rates in a decade, and it's extremely encouraging to see young people leading the progress towards a smokefree Aotearoa."
The fall in smoking was alongside an increase in daily vaping from 3.1 per cent in 2019 to 9.6 per cent in 2021.
While vaping only poses a small fraction of risk, Hart said the organisation does not want teenagers taking up vaping.
However, she said like teenagers in past years, this generation wants to experiment and have fun.
Forty per cent of vape users said their reason for vaping was "just to give it a try", while 15 per cent said they "enjoy it" and 16.1 per cent of daily vapers said they vaped to "quit" or "cut down smoking cigarettes".
Over 75 per cent of students are getting vapes from either friends, older people or family, while 7.6 per cent of those who regularly vape say their main source of vapes is a vape shop, dairy or online.
"The most important thing we can do for our teenagers is to help them make good choices for themselves.
"The Government's recently introduced vaping regulations will further protect teenagers by banning vaping advertising and sponsorship, and sales to young people," Hart said.
Meanwhile, just over one in five students reported being exposed to smoking at least once in their homes in the past week, while 14.7 per cent said they were exposed to smoking in a car or van over the past week, a slight decrease from 2019 which reported 15.4 per cent.