Twenty years ago last week the educational landscape changed. Ken-neth Baker’s Education Reform Act, the most comprehensive and controversial piece of education legislation since the second world war, became law. I did not know it at the time but my life was about to move on, too.

Naturally, most teachers were deeply suspicious. They dismissed the idea of a national curriculum to be defined by politicians as an intrusion into their professional domain. They hated the introduction of national curriculum tests to be taken by children at seven, 11 and 14, and they hated the prospect of inspections every six years, with more published reports .

The idea that heads should take greater financial responsibility for their schools was more welcome, and entrepreneurial head teachers could see that the introduction of a new category of grant-main-tained schools could free them from the clutches of local authority bureaucrats.

Most, though, were nervous of this new independence. They may not have liked their local education authority, but they liked the idea of standing on their own two feet even less.

My reaction was more positive. The basic logic seemed right to me. Why shouldn’t parliament set out what it expected the nation’s children to be taught? Given that broad specification, why not devolve as much responsibility as possible to the individual school to take financial and educational decisions that made sense in its particular circum-stance? And why not hold schools accountable, through tests and inspections, for the quality of those decisions and the standards achieved by their pupils?

The devil, as always, would be in the detail, but there was nothing here that was not good management practice. Tell people what you want them to do, give them the resources and space to get on with it and hold them accountable. I hoped, too, that a national curriculum would mean a national entitlement to study a broad range of subjects, ending what can only be called the eccentricity of local provision in many schools.

I thought it would raise expectations in those schools that did not demand enough of their pupils. Likewise the prospect of real accountability and, yes, the danger of public humiliation might focus a few minds that needed focusing. And, working as I was in a local authority, I was only too aware of both bureaucratic waste and the eccentricity of some local politicians.

A couple of years later I found myself in charge of the national curriculum. Then in 1992, when responsibilities for the curriculum were merged with testing, I headed up the new School Curriculum and Assessment Authority. Later I took over Ofsted, the inspectorate. That is what I mean when I say my life changed. I became responsible at different times for most of the key aspects of the act.

I have therefore to ask myself a difficult question. How much am I to blame for the failure of a series of educational reforms that in principle I continue to believe make basic sense, but which in practice I now consider to have done more harm than good?

If David Cameron and his Conservatives were to ask me what to do about it all, I would tell them to abolish both the national curriculum and Ofsted. The tests at 11 and perhaps at seven should be kept but are in need of radical reform, as is the so-called autonomy of schools. The idea behind the act was that they should be autonomous institutions, free from local authority and central government control, but the tentacles of bureaucratic control are as strong now as they were in 1988 – stronger perhaps.

Baker and subsequent Conservative politicians saw the national curriculum as a challenge to progressive, child-centred educational theories. So the English curriculum insisted on the teaching of spelling and grammar and listed the classics of English literature that should be taught to pupils as they moved through school. The history programme of study sought to ensure that children learnt something at least of the nation’s story – and geography, in a similar fashion, focused on a fair number of geographical facts.

My own view was that these were much-needed developments but, as the years have gone by, the original knowledge-based core of the curriculum has come under ever greater attack. With hindsight, what has happened is utterly predictable.

The national curriculum now enshrines the very educational beliefs it was originally intended to confront. Hence my belief that it has become part of the problem and should be abolished.

Inspections made a contribution when they focused in a rigorously objective way on what matters most in a school: the quality of leadership and teaching. Now they are based on the school’s own self-evaluation, teachers are rarely observed and the evidence from inspection seems more often than not to be used to buttress ministerial claims that everything is progressing wonderfully. Once again a good idea has been rendered impotent, if not downright dangerous.

The tests, in particular those sat by 11-year-olds, matter because they give parents some sense of how successful the school their child attends, or might attend, is in teaching basic skills of English and mathematics. But at the moment, as we all know from news reports, the testing system is in chaos, so even here it is hard to say the reform act initiated a change that has survived the years.

I tried in the different jobs I did to insist on what I thought mattered. Many people of course disagreed with what I wanted to achieve, but not many have accused me of failing to fight my corner. I fought and perhaps I should have fought harder. But in the end, whatever I did or anybody else tries to do in the future, my conclusion is that any attempt to reform the nation’s 24,000 schools from the centre is doomed to failure.

Our current government is never going to deviate from its centralist path. Cameron could. He could develop a truly Conservative approach to state education that finds ways to empower parents as consumers and relies on the wisdom of their choices. That is the prize. The history of the past 20 years shows there is no alternative.

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