Labour has opened up a debate  about the government’s academies and free school programme this week. Rafael Behr described it  as "neither a capitulation to Gove's agenda nor a ferocious reaction against it." But across the political divide, there is an elephant in the room for whoever wins the next election.
The biggest challenge for both Michael Gove and Stephen Twigg is how to ensure proper oversight of so many autonomous schools. We now have a situation where the Department for Education is required to deal with an under-performing academy, but there are already signs that the department is too remote and overstretched to do so. A handful of civil servants in Whitehall are now responsible for overseeing 3,000 schools, something that was previously done by local authorities.
The academies and free school programme is a force for good. The first wave of academy schools created a series of strong institutions, serving communities that did not have access to high-quality school places. They have helped to transform inner-city neighbourhoods such as Hackney, which were previously mired by sink schools and middle class flight. They build on the progressive principle that the state works best through strong independent institutions serving their local area, free to innovate to meet local needs.
The public education system is richer and more innovative with these new school providers. Free schools such as School 21  in Newham and the Greenwich Free School  are adapting their curriculum and delivering classes in new and exciting ways. Where there is a lack of good school places - and that means places of a high enough standard to meet parental aspirations and community expectations - it is right that new schools can be set up.
But the government’s rapid and uncontrolled expansion of academies over the last two years has created a number of tensions that need to be resolved. Twigg has rightly pointed out that the government needs to be clearer about which freedoms are best for driving up standards in schools. It is a good idea to give schools more space to design their school day or the curriculum they teach. But there is little justification for allowing schools to hire unqualified teachers  or serve unhealthy school meals.
Ensuring that all schools employ qualified teachers would be a positive move. In the world's top education systems, the best graduates go into teaching. In Finland, teaching is a skilled profession that requires a master's degree, not one for the unqualified. Gove’s decision to give schools freedom to hire unqualified teachers was a retrograde step that will only harm standards.
Last year, 14 of Gove’s new flagship 'convertor academies' fell below  the minimum performance target and there have been reports of financial mishandling  by academy chains. This is a problem because the government does not have a programme for dealing with academies that are failing or for monitoring the performance of chains. We need a more robust system in place to deal with poor school performance.
The world’s leading school systems all have some sort of 'middle tier ' of governance between central government and a school headteacher. This middle tier is important for monitoring standards, managing the local schools market, and providing a mixture of support and challenge to help schools improve. In Canada it is done by a local schools superintendent, usually an outstanding headteacher that has been promoted to oversee schools in their area. In a report published tomorrow, IPPR  recommends that England should follow a similar model by creating local school commissioners. These would be education experts, appointed at arms length by local authorities, who can monitor and support schools to improve. They would act as champions for parents and standards, with statutory duties to respond to parental demand and to intervene to tackle failure or under-achievement.
Free schools and academies have the potential to transform the school system but they need more robust oversight, with proper systems in place to deal with poor performance. Creating this effective middle tier will be a key challenge for whoever wins the next election.