David Cameron has pledged to tackle "coasting comprehensives" schools which "muddle through" by publishing new league tables.
The prime minister has identified a "hidden crisis" in state schools in wealthy areas and inner cities where students are failing to live up to their potential.
And he says that mediocre schools will no longer be tolerated - and nor will pupils updating their Facebook statuses in class.
“Why should we put up with a school content to let a child sit at the back of the class, swapping Facebook updates? Or one where pupils and staff count down the hours to the end of term without ever asking why B grades can’t be turned into As. Britain can’t let weak schools smother children’s potential", Cameron writes in the Daily Telegraph.
And the PM promises that Sir Michael Wilshaw, the new head of Ofsted "has coasting schools in his sights".
New league tables, published by the government from January and June will help the public "confront failure where it exists".
"The point of education is to change lives. It’s not good enough for teachers in shire counties to be satisfied with half of children getting five good GCSEs, when Mossbourne Academy achieves 82 per cent in Hackney", Cameron writes.
In a speech in September Cameron outlined his commitment to improve education through firming-up discipline and standards.
"Every year that passes without proper reform, is another year that tens of thousands of teenagers leave school without the qualifications they really need", the prime minister said.