Four hundred primary schools that are judged to be among the weakest in England and Wales are to be taken out of the control of their local authorities and turned into academy schools, David Cameron has announced.
The Cabinet is due to discuss primary education on Monday when it holds one of its occasional out-of-London meetings, at an academy school in the West Midlands.
Academy schools were pioneered by the Labour government when Tony Blair's former adviser Andrew Adonis was in charge of education, and their cause has been taken up enthusiastically by the current Education Secretary, Michael Gove.
In 2010, there were 203 academies, all secondary schools. Now, there are 2,456, with another 823 in the pipeline.
Mr Cameron said: "Time and time again we have seen how academies, with their freedom to innovate, inspire and raise standards, are fuelling aspirations and helping to spread success.
"So now, we want to go further, faster, with 400 more under-performing primary schools paired up with a sponsor and either open or well on their way to becoming an academy by the end of next year.
"It is simply not good enough that some children are left to struggle in failing schools, when they could be given the chance to shine."
But Christine Blower, the general secretary of the National Union of Teachers, said: "There is no evidence to show that academy status will bring any educational benefits. Despite this, the Government is removing schools from their local authority and handing them over to unelected sponsors. This is irresponsible and rash behaviour from a coalition whose motivation appears ever clearer to be the privatisation of our education system at whatever cost."