Cameron's schools plans attacked

Mr Cameron said he wanted more secondary schools to group pupils into ability "sets" and all primary schools to use the traditional method of teaching reading known as "phonics".

And he promised to improve inner city education through privately backed academies - a plan based on the Government's existing reforms.

Speaking at the Mossbourne Academy in Hackney, east London, Mr Cameron said: "We must not tolerate a situation where good education is unevenly spread."

He said it was crucial to make sure that "children are taught at the right level for their ability" and not pretend that "all kids are the same".

A Conservative "green paper" specified that this would involve "setting by ability", with pupils divided into top sets for the brightest and lower sets for children who struggle and need extra help.

The document said mixed-ability classes were "boring the most able children and baffling the least able", leading to disruption in class.

But school heads and teachers criticised the plan. John Dunford, general secretary of the Association of School and College Leaders, said: "Dividing students into ability groups in all subjects, with lots of small groups, would be hugely impractical, not to mention expensive and unnecessary.

"It is hugely ironic, and disappointing, that a political party which says that it wants to free heads from government control is telling them how to organise their schools in this detail."

But Philip Parkin, general secretary of the Professional Association of Teachers, said the policies were "disappointingly familiar". Steve Sinnott, general secretary of the National Union of Teachers, described some of the proposals as "hardly new".