The key questions about academies - old and new - explained.What is an academy?
Academies are independent, state-funded schools, which receive their funding directly from central government, rather than through a local authority.
They have more freedom than other state schools over their finances, curriculum, length of terms and school days and do not need to follow national pay and conditions for teachers.
Academies were originally a Labour policy designed to improve struggling schools, primarily in deprived areas. But this has been changed radically and accelerated by the Conservative-Liberal Democrat coalition.
How has the policy changed?
All schools - primary as well as secondary - have been invited to convert to Academy status, but priority is being given to those deemed by education watchdog Ofsted to be "outstanding" or "performing well".
Other schools can also they apply but have to do so in a formal partnership with another good school.
So in a sense the new policy is about spreading good practice from the best schools.
Education Secretary Michael Gove says academies will drive up standards by putting more power in the hands of head teachers and cutting bureaucracy, and claims they have been shown to improve twice as fast as other state schools.How many are there?
As of 1 May 2012, there are 1807 academies open in England
The number has grown dramatically under the coalition government, from 203 in May 2010.What were academies like before the change of government?
Labour-style academies were attempt to give a fresh start and new impetus to a struggling schools. Local businesses, philanthropists and educational charities were involved as sponsors. And originally these had to contribute £2m to the cost of new schools.
These schools were usually new-builds with state-of-the-art facilities and a new name. But ultimately the financial requirement was dropped by Labour, who broadened out the range of people who could sponsor academies. Then the coalition government ditched the requirement for a sponsor.
How do schools benefit from becoming academies?
On top of the £25,000 towards conversion costs from the Department for Education, Academies can potentially top up their budget by as much as 10%. This is because on top of the regular per pupil funding, it gets money that would previously have been held back by the local authority.
Councils use this to provide services, such as special needs support, to schools across the borough.
If the school is able to buy in the services it needs more cheaply, or has less need of those services, it can benefit financially from becoming an academy. Now large academy chains runs schools creating economies of scale themselves.
More freedom over staff pay can mean they make savings or attract and retain good teachers by paying more, while control over the length of the school day can allow them to teach more lessons.What do critics say?
Teaching unions say it will fracture the state education system and open the door to privatisation - private providers already run large "chains" of schools.
Labour says the changes will benefit more privileged neighbourhoods and that the best schools will be able to suck in the best teachers and resources, leaving those left under local authority control being regarded as second best.
Critics also say that the ability of local councils to provide support services for schools will be weakened by the money being lost to the Academies fund.
Teachers have held strikes against conversions in several schools, angered by the fact that national pay agreements negotiated by their unions could no longer apply.How accountable are academies?
They are subject to inspections by Ofsted, like other schools. However, a substantial chunk of new converters will be outstanding schools - which will no longer be subject to routine inspections under separate changes made to the education inspection regime.
The DfE publishes their exam results and other data from Academies as it does for other schools.
Opponents of the policy argue they are less accountable than other state schools, because they are not overseen by the elected local authority leaders - although they do answer directly to the education secretary.How do schools become academies?
Schools submit their application to the DfE once they have a positive vote for the change from their governing body.
Once the application is approved, the Secretary of State issues an academy order and a trust is then set up which in effect has a contract to run the academy for the government.
The school then registers the academy trust with Companies House and agrees leasing arrangements for school buildings and land. The final stage is the signing of the Funding Agreement with the secretary of state.
Schools must hold some form of consultation before the funding agreement is signed. But some teachers' unions have criticised the fact that it has been left up to the school to decide who is consulted, and when and how this is done.
The school does not need the permission of the local authority to convert.Do they follow the same rules on admissions and exclusions?
Yes. Academies are subject to the same admissions code as other state schools, but academy trusts become the admissions authorities for their schools - rather than the local authority.
This means the academy can, like a faith school, set its own criteria for awarding places if it is oversubscribed.
Also, schools with specialisms are allowed to select up to 10% of their pupils on the basis of their aptitude for a particular subject, such as music, and many academies fall into this category.
Academies have to follow the law and government guidance on excluding pupils, but they do not have to consult the local authority before deciding to exclude a pupil and they can arrange their own independent appeals panel.