What equals a free education?

What do you get if you add half a coconut to an apple and two bananas? This is not a recipe for the latest craze in smoothies, but a maths brain-teaser that has swept the internet this week.

The children's puzzle is based around a basic mathematical equation using a range of fruits and asks you to decipher which number each fruit symbolises, similar to algebra, then work out the total. Reportedly the puzzle was leaving adults flummoxed as to the correct answer.

It could possibly leave many children baffled, too.

Last week the OECD released the report, Low-Performing Students - Why They Fall Behind and How To Help Them Succeed. It showed New Zealand children from poor families were more than six times more likely to do badly at maths than children from well-off families.

Among OECD countries, only Israel, Poland and Ireland performed worse. This report said socio-economic status was "probably the most important risk factor associated with low academic performance" around the world. Other factors also contributed to poor performance, like whether a child came from a single-parent family or had any early childhood education.

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One might hope that the inequity of a child's background could be levelled out by an education system that is free for all. That was certainly my own educational experience back many years ago in the UK, and one I can be forever grateful for.

As a child of a single parent growing up in one of the most socio-economically deprived suburbs of Liverpool, thanks to a free education system and great teachers, I was able to get into Oxford University alongside superwealthy children who had had a privileged upbringing and private education. While not quite Slumdog Millionaire, I was a walking example of the theory of renowned educationist Paulo Freire, that education sets you free, that education is freedom.

How idealistic of me.

The reality in New Zealand today is that education is not free.

Will I be using my own experience to encourage my children into tertiary education?

No. In fact, unless they want to do a job which requires a degree like law or medicine, I will be actively dissuading them from going to university and saddling themselves with huge debts. Instead, I will be encouraging them to do the best learning they can at school and then to leave for an apprenticeship ... or marry someone rich.

I do not agree with Labour's proposed policy of free tertiary education. In my view it will just swamp the market with more people with non-prescriptive degrees who cannot get jobs.

Instead, I would prefer our taxes be diverted into better funding of our primary and secondary education systems so that they can be fairer to all.

New statistics have shown that for a child starting school in 2016, a state-provided "free" education will cost around $35,000. Parents of children born this year will pay around $37,000 by the time they finish school in 2033. The figures, compiled from a survey of more than 1000 members of ASG Education Programmes, included fees, transport, uniforms, computers and sports trips associated with 13 years of schooling.

A current University of Otago study is investigating the stress parents face over the increasing cost of modern state education, with parents increasingly concerned to spare their children any embarrassment and even bullying for not being able to join in with their peers in paid school activities.

While my maths may not be strong enough to solve the fruit brain teaser, it is strong enough to realise that in 2016 parents are expected to pay for many things that were once free in schools, like swimming lessons, music and sport and computers. Heck, there were even tissues on my children's stationery lists. I should feel lucky they provide toilet paper.

This is not the fault of schools or the hard-working teachers who are working in ever more difficult circumstance.

If so much has to be passed on to parents it seems clear schools are underfunded.

It is reasonable to expect parents to contribute and get involved in their children's education, but there is a difference between parents helping out in classes and camps, and being involved in school fundraising to more substantial contributions where parents are funding things like school buildings and security systems and essential education.

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This month we reported that parents in the wider Bay of Plenty region pay more than $6 million a year towards their children's education, with New Zealand Principals' Federation national president Iain Taylor saying many schools had become reliant on school donations because funding levels were not covering basic operation costs.

At the beginning of the year NZME reported that Ministry of Education figures showed nationwide donations and fundraising went up $1.2 million from 2013 to 2014, reaching $161.6 million. That's $8.4 million more for New Zealand schools than in 2010.

Education Minister Hekia Parata has made much of the choice regarding paying donations. But it is not so much a choice as simply what parents can or cannot afford which makes for an inequity as the wealthiest schools attract the most money. Epsom Girls' Grammar in Auckland banked $2.5 million. Although higher-decile schools receive less funding this hardly levels the playing field.

Our current system in my view just perpetuates the inequality of social and economic circumstances that a child is born into. That is not to say that parents should not be allowed to contribute extra where able - of course they should have this choice. But they should, in my view, be voluntary extras and not positioned as essential funding. The fact that some parents can contribute a lot to schools should not mean that other schools are underfunded or some children miss out.

Here's a brain-teaser: Section three of the Education Act 1989 says "every person who is not an international student is entitled to free enrolment and free education at any state school" between the ages of 5 and 19.

Investing in education would reap significant socio-economic benefits long term for individuals and our communities.

Education is not free. Here's the solution: Our schools need a better funding system that is fairer to all.