John Rentoul: Children reap fruit of Labour's revolution

New evidence now unambiguously confirms that academies have transformed education

This is not a new observation, but politicians tend to be in a hurry. For them, short term means Twitter and blogs, medium term means next week's media bookings and long term means the election. The reform of public services, though, runs on a longer cycle. I remember Tony Blair in 1996 promising Anne McElvoy, parent-to-be, Islington resident and political commentator, that if he had two terms in government, she would be able to send any children she might have to "good state schools in the borough".

We are not quite there yet. But now, 14 years later, there are at last signs that a revolution in English schools is gathering pace. A third of all secondary schools are either academies, or converting to academies, the Department for Education reported last week. Suddenly it looks as if academy schools will be the norm by the next election – that is, in the politicians' long term.

This is an unheralded transformation. Over the coalition's first year, most media shoutiness has been about "free schools", which are mostly small new schools set up by groups of parents. They are like academies but there are only 16 of them. Historians will note the big change: that most secondaries, and probably most primary schools, will be out of local council control by 2015.

Something else happened last week: a breakthrough in rigorous assessment of the academies experiment. A study by Stephen Machin and James Vernoit at the London School of Economics found three things. First, that academy status tends to raise pupil performance. This had been pretty obvious from comparing the results of academies with those of their predecessor schools, but previous studies had not satisfied the test of statistical significance, partly because there have been so few academies open for long enough. Now there is no doubt. "Academy conversion generates... a significant improvement in pupil performance," the authors conclude.

The second finding confirms the first, and also confirms what we already know. It is that converting to an academy tends to raise the quality of a school's intake. It was always one of the strongest arguments for academies that they were oversubscribed – that parents were clamouring to get their children into schools that they previously shunned. Opponents of academies have always dismissed their better results by saying that they achieved them by creaming off the more able children in their area. Machin and Vernoit refute this: "The performance improvements cannot be explained by the increased prevalence of higher ability pupils in the academies."

The increase in higher ability pupils is a symptom of success, not its cause. Six years after the doctrine was first enunciated by the deputy prime minister, Prescottism is dead. It was John Prescott who should have discredited the cause of educational conservatism by declaring: "If you set up a school and it becomes a good school, the great danger is that's the place they want to go to."

The most dogmatic of conservatives will have to accept now that if middle-class parents are more likely to want to send their children to an academy because it obtains better results, that is not a "great danger", but what success looks like.

The third finding, though, is the real dynamite under the rampart of educational conservatism. It is that academies also tend to raise pupil performance in neighbouring schools. The improvements are smaller, but still significant. This destroys the last part of the argument of the opponents of academies, which was that they achieved better results only at the expense of other local schools, either by poaching the more able pupils or by demoralising staff and pupils at neighbouring schools.

Until now, opponents of academies were able to peddle defeatism, saying that the success of one school would demotivate others. Instead, the opposite seems to happen: that the success of one school spurs staff and pupils at other local schools to try harder. Competition is finally, cautiously and emphatically vindicated in schools reform.

At long last, the Blairite revolution in secondary education is coming to fruition. Interestingly, it is Michael Gove, that most Blairite of Conservative ministers, who will take the merit award. But the true author of the revolution is Andrew Adonis, Tony Blair's policy adviser from 1998 and schools minister from 2005 to 2008. The idea of academy schools was first devised by Adonis in No 10 in 2000 as Blair sought a programme of public service reform based on choice.

The first academy schools did not open until September 2002, well into Blair's second term. When Blair left office, there were still only 46 academies. Fortunately, Gordon Brown kept Adonis on and, by the time he left the education department, there were 130 academies. That, it turned out, was the critical mass. Now there are 658, with 1,000 applications pending.

Changing an entire schools system takes a long time. Machin and Vernoit say that one of the reasons why the benefits had not been definite in previous studies is that they have "taken a while to materialise". They add: "These results are strongest for the schools that have been academies for longer and for those who experienced the largest increase in their school autonomy."

So it is that academy schools are used for photo-opportunities by short-term politicians. Barack Obama (up for re-election next year) played whiff-whaff with David Cameron (in four years' time) at the Globe Academy, Southwark.

The man who made it possible, and who should take the credit for rising standards in secondary schools over the next few years, is the one who sat in the front row for President Obama's speech, chatting to Gordon Brown as if nothing had happened. Tony Blair looked like someone from long ago, but his presence in Westminster Hall on Wednesday should remind the Labour Party of what it has lost.

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