Sunday's "Save our charter schools march" was a moving experience. It wasn't just the hundreds of people who turned up in torrential rain to protest. Nor was it ACT leader David Seymour's impassioned chanting. Nor even the Vanguard school students' valiant haka.

What was moving was the procession of young students, mostly Māori and Pasifika, who strode forward, proudly, to the microphone. If their eagerness to speak caught the protest organisers by surprise, their words did not. They had only one message: a plea to the prime minister and Minister of Education Chris Hipkins not to close their schools.

One student explained that she had been failing at her state school and that she had nothing to live for after her friend had committed suicide. Another described the self-destructive path he had been following at his old school.

And a former charter school head-girl told us how she had felt worthless before starting at her new charter school. The young woman – now a scholarship winner – apologised as she started to speak, saying she was "no politician". Someone in the crowd called out, "Not yet!"

A young man I spoke to said his new school was different because the teachers all cared. He mattered to them, and he felt determined to live up to their expectations.

Each of them had found a sense of purpose at their schools – and a sense of family in the unique environments created by the schools. And all had clearly thrived.

But if their pride in their schools came through, so did their sense of bewilderment. And of betrayal. As one grandmother said, she thought the new Government wanted to put children first. How could it be in the interests of children for the Government to close their schools – schools that were helping them succeed where their old schools had failed?

It is a good question. Especially when our education system is not just failing a few of our children, but thousands of them. New Zealand's long tail of educational under-achievement is a national disgrace.

Our state system too readily tolerates low expectations. It should be no surprise that so many students live up to them.

New Zealand's problems are not unique. State schooling is failing the poorest communities in many Western countries.

With the status quo not working, educationalists around the globe have sought new solutions. And in England, after five years of the policy, Free Schools (as they are known there) are now the highest performing category of state schools in that country.

New Zealand's charter schools movement was born out of this same quest. Freed from some of the shackles of the state system, charter schools offer a new kind of publicly funded, independently managed school. They permit educational entrepreneurs to trial new and better ideas. If successful, those ideas can then be scaled up – or transferred back to the regular state school system.

Of course, with innovation comes risk of failure. And one of New Zealand's new charter schools was a failure. But unlike its failing state school counterparts, it was quickly shut down.

But the other charter schools have all thrived. They have found ways of encouraging success where the regular state system has failed.

The results of that success were evident at Sunday's protest march. They can also be seen in the NCEA pass marks of schools like Vanguard Military which, for Year 12 in 2016, achieved a roll-based NCEA Level 2 achievement rate of 94 per cent. And this with a roll drawn from some of New Zealand's poorest communities.

Against this backdrop, it is not obvious why the new education minister is so determined to put an end to New Zealand's charter schools model and, to quote his January cabinet paper, "close these charter schools in their current form".

And to do so without having even visited one of them.

Could the answer lie in misplaced loyalties? Teachers at charter schools are not required to be registered and the schools are bulk funded. These arrangements permit the schools to hire teachers on different contracts to those in regular state schools, to pay teachers more (or less), and to hire specialist teachers from outside the regulated profession.

Each of these freedoms is a threat to the teachers' unions' collective bargaining powers. As a consequence, the teachers' unions have been vocal opponents of the charter schools policy. No one can blame them for that. That is their job.

But our state education system does not exist for the benefit of teachers – or their unions – any more than the legal system exists for the benefit of the Law Society, or the health system for doctors.

Instead, our education system exists to serves its students – our children. And their futures depend upon the system being flexible and innovative enough to accommodate their needs.

While it is possible some of the current charter schools may yet transition to become some other form of new school within the state system, there is no certainty of this.

And if the state system had the flexibility to produce – and sustain – schools with the special character of the charter schools, there would have been no need of the charter schools model in the first place.

There is a lesson in all this for Mr Hipkins. If he won't hear it from his political opponents, let's hope he will from the children his ministry exists to serve.

After all, they are the same children his prime minister has promised to lift out of poverty. Helping them achieve educational success must surely be the best place to start.