Footage obtained by hidden 1 NEWS cameras shows how easy it can be for minors to buy vaping products.
School leaders say the habit's become rife amongst students, and businesses not following the rules are adding to the problem.
1 NEWS spoke with Hayden Kingdon, associate headmaster of Auckland's St Peter's College.
"We're frustrated because some businesses are selling what is an R18 product," he said.
1 NEWS sent a minor into six stores in Auckland; three refused to sell him vaping liquid for not having ID, but three didn't check his age and made the sale.
Those who were caught selling to our minor disputed the sale ever happened, saying they always checked for ID.
The new laws came into place in November last year, making it illegal to sell e-cigarettes and liquid to minors, whether or not the product contains nicotine.
But some businesses not yet checking for ID could get away with it for now.
"These are new laws, we have an initial phase of educating retailers about the laws and then we'll move onto enforcement," Associate Health Minister Ayesha Verrall told 1 NEWS.
The minister said while they've carried numerous covert stings on businesses for the sales of cigarettes, they were yet to carry out stings for vaping.
Shayne Nahu, chief executive of The Cancer Society said some of his health promotions staff have approached schools with major concerns.
"They've been so worried by the increase in vaping happening in their schools, they're asking if they can come in and help them with ways of prevention messaging."
But in some cases, it's already gotten out of hand.
"What's even more concerning, they're asking if they've got any way they can help schools get assistance to help kids quit vaping," he told 1 NEWS.
He said he's aware of one school that's had to close one of their toilet blocks because staff are concerned it's being used as a 'vaping hangout' at lunchtimes.
Vaping has largely been pitched as a quit-tool for smokers. And while e-cigarettes have far less chemicals than regular cigarettes, the long term effects are not yet known.
Dr Kelly Burrowes of Auckland University's BioEngineering Institute is three months into a three-year study into the effects of vaping.
"We're exposing some cells to the chemicals from an e-cigarette; we're doing that by blowing the liquid to simulate the inhalation of the average person vaping."
Burrowes said early indications show it's changing how the air and blood are flowing in lungs, in a similar way to smoking-related diseases.
"We already know there are heavy metals that come off the parts of the e-cigarette from the coil and there are compounds that create that from the heating process so there could be things like formaldehyde which is a known dangerous carcinogenic," she said.
When asked if she thought it was more dangerous than smoking, she said she was unsure, but that already the science is showing there are going to be harmful effects.
"It worries me that youths are picking this up — with younger brains they've got a higher chance of becoming addicted to nicotine so if they start vaping at a younger age there is a chance they will continue using it, and some studies have shown they're more inclined to pick up smoking."
Last month the Government brought in mandatory 'no vaping' signs to be displayed in schools, kura kaupapa, kohanga reo and early childhood facilities. This means these places must be smoke-free and vape free indoors and outdoors at all times.
It's just part of multiple incremental changes happening over the coming months.
Kingdon said some conversations are being held in classrooms and assemblies to make students aware of the potential harmful effects.
"I think it's very important that the students understand that this is an R18 product for a reason. The Ministry of Health has said this is not risk free, there are long term consequences that at this stage we don't know and most importantly is the nicotine which is a highly addictive substance so we're telling our students they need to be very very careful and it's not for them and it's for a very good reason."