Ofsted’s new Chief Inspector, Sir Michael Wilshaw, who took up his post in January, has announced plans to introduce ‘no-notice’ inspections for all regular school inspections from September 2012.

Sir Michael was knighted for his services to education in 2000 and, before his appointment as Chief Inspector, was head teacher of Mossbourne Academy – which opened on the site of a failing school. He raised standards by imposing strict discipline and robust performance management systems and has subsequently seen 82% of pupils receive five good GCSEs including English and maths this year and an ‘outstanding' rating from Ofsted.

Sir Michael has made no secret that he wishes to challenge England’s schools to do better, particularly as a result of the UK falling behind comparable nations in international league tables. He said "I was shocked to read that only 4% of schools are judged outstanding in teaching, yet 20% are outstanding overall … Have we gone for the soft option too often? Yes we have. At 15, we're two years behind China in maths. We as a nation should be alarmed."

Ofsted already undertakes unannounced inspections in a number of circumstances, including where concerns are raised about a school and for some satisfactory schools that do not show enough capacity to improve.

Speaking about the plans, Sir Michael said, “Ofsted has been moving towards a position of unannounced school inspection over a period of years. I believe the time is now right for us to take that final step and make sure that for every school we visit inspectors are seeing schools as they really are in the corridors, classrooms and staff room.”

“Ofsted already has considerable experience in undertaking unannounced inspections and we know it works. With this further change, parents and all those interested in what is happening in our schools can have absolute confidence in Ofsted’s findings.”

Since the first Ofsted school inspections in 1992 there has been a steady journey towards unannounced visits. Initially, schools received over a year’s notice of inspectors turning up. Over time this shifted to six to eight weeks’ notice and then, from 2005, around two days.

Brian Lightman, General Secretary of the Association of School and College Leaders, has expressed his concerns about the move towards ‘no-notice’ inspections. “We welcome moves to improve the effectiveness of inspection, but I have real doubts that ‘no-notice’ inspection will accomplish this,” he said. “An effective inspection system is based on mutual trust and respect, not the premise that schools are trying to ‘cheat’ and need to be caught out. If inspection is going to lead to improvement, it needs to be done with schools rather than used as a beating stick.”

As part of the changes introduced in 2009, Ofsted consulted extensively on ‘no-notice’ inspections and also piloted unannounced visits. An Ofsted spokesperson said, “We found a great deal of support for the move. At that time, however, we could not overcome the important issue of being able to get parents’ views as part of the process. With the introduction of our new Parent View online questionnaire last year, parents can now share their opinions of their child’s school at any time, making a move to ‘no-notice’ inspections possible.”

The details of how the changes will work will form part of a wider consultation on the future of inspection that will be announced in coming weeks.