In 2017, 2491 five-year-olds were enrolled in early childhood education (ECE) - a 17 percent increase since 2015.
That is despite the total number of kids who turned five in both those years, staying close to 65,000.
Pepper Menzies is five, and one of four five-year-olds at Naenae kindergarten in Lower Hutt.
Her mum Greta Menzies said even though Pepper wanted to stay at kindy, she initially did not think the option was realistic and was worried about the stigma attached.
"The only reason that I was going to send her to school was that I thought it'd weird for her - and for all the other kids - if she stayed at kindy. It would be cool if there was more of a culture of staying so it wouldn't be sticking out like a sore thumb."
Ms Menzies said the decision to keep Pepper in kindergarten was because of the strong, play-based learning philosophy of the kindergarten.
Melanie Wenger's daughter is also five and at Naenae kindy.
She said the decision to stay on was about fostering learning, not stalling it.
"I think there's more value in my daughter doing things that she's interested in rather than following a script.
"Children have an inbuilt curiosity and it's all about protecting that love of learning, once it becomes mandatory it no longer has its spark," Mrs Wenger said.
"At school, I always felt like when I was getting really into something, I was just shuffled along to the next thing and sometimes it was just so gutting.
"Kindy just offers that freedom to spend endless time doing what you love."
Not everyone understood her decision, Mrs Wenger said.
"At first I was met with a 'not many people do that' sort of response, and I felt really like I was the black sheep and it almost put me off. But, I persevered and did some more research and I don't think that there's any harm in waiting."
Naenae kindergarten head teacher Maureen Wilson said most parents did not consider it an option to keep their five-year-old in ECE, even though a child does not legally have to be enrolled in school until six.
She said word of mouth was one of the main reasons it had escalated at their centre.
"We have noticed a trend here. It started off with one family in particular and it's grown since then.
"People have started to ask more questions about it, and now we've had three or four more families interested in it."
Ms Wilson said there was a stigma attached, but it was starting to change.
There were many reasons a parent might decide to keep their child in ECE, but ultimately it came down to being informed and understanding what the best learning environment was for a child, she said.
New Zealand Educational Institute president Lynda Stuart said while the union had not noticed an increase in six-year olds starting school for the first time, elements of early childhood education were becoming more common in primary schools.
She said since the government announced it was dropping national standards, teachers felt free to take a more holistic approach to teaching. This included more play-based learning - like what children do at ECE.
Ms Stuart said broadly, it was a shift from children needing to be school ready, to schools being child-ready.
Ms Wilson said the ECE sector had seen this, with primary school teachers coming to her kindergarten for planning ideas.
"One new entrant teacher has come and borrowed a copy of our curriculum to help her with some of her planning, she's also taken some ideas from here of things we do around water play and sand play and the value of that and what children learn which is amazing, it's just so exciting."
Next term, Ms Wilson is starting a research project about older children at pre-school.
She will also be talking about it with other teachers at an international conference later in the year, in Bali.
-reprinted from RadioNZ