A friend of mine, a committed Christian, sent me this story [3] about how taxpayer dollars are being used to teach kids in Louisiana all sorts of wacky things. America's 'voucher schools' – rather like Britain's new Academies and Free Schools – manage themselves, though the cost of the education they provide is subsidised by taxpayers. The aim is to give parents choice and the benefits of real competition between independent school providers, while making sure that every child has access to education, no matter how rich or poor their parents might be.

A noble ambition. But what happens if schools teach creationism, say? Or for that matter, promote Islamic fundamentalism? Denmark, which has had the same sort of private-provision/public-finance model for decades, used to have so-called 'Red' schools, which promoted socialist thinking. Are such things a legitimate use of taxpayer cash, however much the parents in question might actively seek out schools teaching such stuff?

It's an interesting problem. The libertarian view would be that the state shouldn't be involved in education at all. Education departments in Britain and America, certainly – and probably in most other countries – have not added at all to the quality of education, nor to children's access to it, say libertarians. Most kids got a good education long before the state got involved. Parents in Africa on just a few dollars a day make sacrifices to send their kids to 'penny schools' and consider it a good investment – as Professor James Tooley has documented in great detail [4].

At the other end of the spectrum, look at the disaster of state-financed and state-produced education. It was this model, in the postwar years, that brought us the so-called 'progressive' approach that was so ashamed of what it produced that it did not even publish examination scores – so parents had no way of knowing what state schools were actually doing for their children, if anything. They were expected just to pay up through taxation and let the 'experts' get on with whatever they were doing to their kids. And later, in Britain, we had the utter inanities of the National Curriculum, in which the country's history and culture barely got a look in.

The idea of voucher and quasi-voucher schemes is precisely to break down that kind of state monopoly in eduction. It's reckoned that you cannot do everything at once: so let's free up the supply of schooling first, while still maintaining the guarantee of state support so that nobody is left out. It is actually that model, first introduced in Britain by Mrs Thatcher's government, that brought us the National Curriculum just mentioned. The view was that if taxpayers' money is being used, then the authorities have a right to make sure that it is spent properly. Unfortunately, when you leave it to state providers and state-employed education experts to decide what a 'proper' education is, well, you get a very silly answer.

So should we just leave it for parents to decide? This is probably the leading market-economics answer. Even if the state is paying, so the reasoning goes, parents will tend to make sensible choices for their children, whom they want to succeed. They are not going to choose schools that paddle their kids into some intellectual backwater. And so, like any other competitive market, you will get standards being bid up, and the quality of schooling will improve.

Except that actually, many parents would indeed like their children to be paddled up the backwater. Some fundamentalist families may not wish to see their female offspring learn too much. Others may deeply believe the creationist paradigm and want their children to share it. Some might believe that the Western values that give them the choice of what to learn are fundamentally wicked, and that their children should learn to hate them.

So should the state insist that taxpayers' money should not be spent on such things? To override the wishes of parents is to say that some state 'experts' should decide. And we know where that leads us. So it is not an easy question. On balance, I would say yes, parents should decide; I have faith that the overwhelming majority will make sensible decisions for their children. Better choices, on balance, than the professional state educationalists have made over the last half century.