The best state schools could be allowed to expand to meet demand for pupil places for the first time, it has been revealed.
Plans being drawn up by Education Secretary Michael Gove would see primary and secondary schools that opt to become academies freed from council limits on numbers.
The move is likely to mean successful schools get bigger as more pupils flood in, while poorly-performing schools could see numbers decline sharply and be forced to close.
Complex admissions procedures are also set to be simplified to make them less bureaucratic and easier to understand for parents.
News of the proposals, to be included in a White Paper published in the coming weeks, came as applications closed for places at secondary schools for next September in many parts of England and Wales.
Tens of thousands of children are likely to miss out on their first-choice school because the best are oversubscribed.
The number of pupils that a state school can take is usually set by the local authority, and can be exceeded only in exceptional circumstances. However, there is concern in Whitehall that councils are limiting the success and size of popular schools to stop them draining pupils from inferior schools nearby.
Under the new plans, top schools who take academy status will be able to scrap their fixed admission numbers, as long as there is physical room for extra pupils. This will earn the schools tens of thousands of pounds of extra funding.
Mr Gove hopes the move will force councils to address quickly why schools are failing, and mean there are many more good school places on offer.
Mr Gove wants to simplify the 86-page admissions code, which was toughened up under Labour to stop parents lying about their address or church attendance to secure places for their children. Officials believe it can be made simpler without being watered down.
