Some Kiwi schoolgirls spend over five hours a day on their phones after class

Parents are being told to lead by example following a survey's findings that many Kiwi teens are on their cellphones from after school until they go to bed and most kids have no limits on their screen time.

'We're using our phones everywhere we go - if we want to change we need to start limiting ourselves first', a researcher says. Source: Seven Sharp

Forty per cent of students said they spent time gaming after school, with the keenest gamers high school boys, according to the Census at School survey run by Auckland University's Statistics Department.

The gamers spent an average of two hours in front of their Playstation, Xbox, Nintendo and the like, but a quarter spent four hours or more gaming.  

Of the 70 per cent of students who said they spent time on their phone, the most avid users were high school girls, with 89 per cent on their phones once school was out, and for a median of three hours. 

But a quarter of those girls spent five-and-a-half hours or more, meaning they're on them until bedtime.  

The Ministry of Health recommends that outside school, screen time is kept under two hours. 

The Census at School's co-director, Rachael Cunliffe, told Seven Sharp if adults want kids to change, they should set the example.

I'm not tech savvy to check history - Mother of two Erin McDonald

"We're using our phones at the table and most people are using their phones everywhere they go. So kids are mirroring what the adults are doing. I think if we want our kids to change we need to start limiting ourselves first," she said.

Census at School data also shows that 84% of teens and 63% of younger children say they have "no limits" put on their screen time.

In the survey, a parent or caregiver being in same room as the young person counted as supervision, but only 20 per cent of respondents said this usually happened.

For those children who do have limits, primary schoolers were allowed an average of one hour at the screen and secondary students two hours.

Mother of two Erin McDonald said it's hard to supervise the kids on their screens.

"Unless you're sitting there all the time it's impossible. I'm not tech savvy to check history. My husband possibly could, but he hasn't the time to be checking it either," she said.

The Parenting Place gave Seven Sharp some tips for parents on supervising children on phones and computers.

*Use built in parental controls on websites. They let parents control and limit what their kids are looking at.

*Create a contract for the family and have everyone agree on how much time they all spend in front of screens.

*Lead by example. Parents should show their kids that they're more important than checking the parents' own texts or emails.