David Cameron says he backs Labour's city academy programme - but claims it must go "further and faster".
Mr Cameron met pupils at the London Academy
He says he wants more freedoms for the flagship scheme, which sees private sponsors provide up to £2m, and being given a say in the way they are run.
The academies have attracted criticism and are viewed by some as a threat to the future of state education.
But the Conservative leader said being in opposition was not just about opposing the government.
He and shadow education secretary David Willetts toured new buildings at the London Academy, in Edgware, north London.
"I think in politics you've got to do what is right. I think city academies are right," he said.
"We would like to see it go further and faster. We would like to see academies be given more freedoms.
"We want the academies to be about regenerating the whole area, not being just an island of excellence."
City academies, which replace schools in difficulty, typically cost about £25m.
The government wants 200 academies open or under construction by 2010, saying they want to raise standards in deprived areas.