English schools: 10 years to see big change, says Gove
It will take 10 years for England's position in international education league tables to improve, the minister in charge of schools has told the BBC.
Education Secretary Michael Gove said some changes would happen more quickly, such as discipline and the number of students taking sciences and languages.
But he said major improvements in standards would take a decade to show.
He also says he is prepared to see a fall in the number of A-level passes as the price for making the exams tougher.
Labour has criticised many of Mr Gove's decisions as education secretary, including his flagship free schools policy.
Speaking to the Observer, shadow education secretary Stephen Twigg accused Mr Gove of being "obsessed" with academies and free schools - although he did, for the first time, acknowledge that Labour's school building programme was flawed.
Speaking to the BBC Sunday Politics show, Mr Gove said there were a number of short-term measures he would use to judge the success of his education policies.
These included more students taking "rigorous subjects", more headteachers taking advantage of academy powers, and more independent schools choosing to join the state sector.
But on improving the position in international league tables - which in 2009 put England 25th for reading, 25th for maths and 16th for science - he said that would take longer.
"We do need to climb up that league table, but I think it will take about 10 years before we can begin to see the fruits of all the reforms we're making, which will lead to a turnaround in the league tables," he said.
"The reason for that is the next time that specific measure will be taken it will be students who spent the majority of their time in schools following policies set by the previous administration."
Mr Gove said grade inflation "discredits the integrity of our education system" and GCSEs, A-levels and degrees must get "tougher".
"If that means fewer passes then that's something we'll have to accept, but I want to ensure that as well as exams being tougher, schools work harder," he said.
"What I hope we will see is our exams are once again trusted across the globe and our children are among the best in the world."
Mr Gove said he had floated the idea of having fixed quotas for each grade, but wanted to work with universities on how best to toughen up the exam system.