David Bell, chief inspector, will leave Ofsted next month to run the Department for Education and Skills.

Mr Bell, the 46-year-old son of a Glaswegian railwayman, has enjoyed his time in the limelight as chief inspector and has attracted attention throughout his career - becoming the youngest primary head, youngest chief education officer, youngest council chief executive and youngest chief inspector.

Now he will have to acquire the black arts of mandarindom, of which his predecessor, Sir David Normington, was a master, and wield power from a less public position. He will soon have his work cut out for him as Ruth Kelly, the Education Secretary, will need all the help she can get with her white paper, which is being attacked from all sides, and a major reform of secondary qualifications.

His immediate replacement as chief inspector is Maurice Smith, 50, a former social worker and head of Ofsted’s early years division. Mr Smith, who has never taught, takes on the pound;155,000-a-year post, overseeing Ofsted’s takeover by 2007 of the inspection of children’s social services, the Family Court Advisory and Support Service and further and adult education.

He will be the first chief inspector of schools to have no experience as a classroom teacher.

Described by a source as one of the old school of civil servants, uptight and cautious, Mr Smith spends his spare time refereeing amateur football matches close to his home near Wigan.

But he is widely seen as a stop-gap appointment. An Ofsted spokeswoman said it would begin an open competition in the new year to find a permanent replacement.

Mr Bell, whose two daughters attend state schools, said: “Whilst much has been achieved, there are real challenges across the work of the department which I am looking forward to.”

And he would know. During three-and-a-half years as chief inspector, Mr Bell has not shied away from criticising government strategy or schools’

and teachers’ performances. He published a hard-hitting report on 14-19 education and said that too much emphasis on literacy and numeracy was in danger of creating a two-tier primary curriculum.

His appointment was widely welcomed, from staff at the DfES to teacher union leaders. John Bangs, National Union of Teachers’ head of education, said: “He is a supremely skilful operator and a natural successor to David Normington.” Sir David has moved to the Home Office.

Mr Bell has been credited for overseeing an expansion of the inspectorate, at the same time as implementing staff cuts and seeing through a new inspection framework.

One of the few times his sure foot slipped (he is a keen Scottish country dancer) was when he singled out independent Muslim schools for failing to teach pupils tolerance of other cultures. Despite professing to be taken aback by the media furore, he agreed to tour the TV studios to put his message across. But within days he faced criticism from his own inspectors when The TES revealed that Christian private schools performed even worse.

But Mr Bell’s mistakes are memorable partly because they are so infrequent.

* jon.slater@tes.co.uk