Inspectors have found large regional variations in the standards of behaviour in English schools, a TES analysis shows.
New statistics from Ofsted show big differences in judgments about conduct in the classroom throughout the country.
In England, on average 94 per cent of primary schools, 82 per cent of secondary schools, 92 per cent of special schools and 85 per cent of pupil referral units were rated good or outstanding for behaviour by Ofsted in 2008 to 2010.
But just 67.7 per cent of schools in Yorkshire and the Humber got the top grades, compared with 89.6 per cent in the South West. Almost 85 per cent of schools in the capital were ranked good or outstanding compared with 78.4 per cent in the East Midlands.
The differences are even more stark when individual local authorities are compared. Just a quarter of secondaries in Knowsley and Hull got good or outstanding, compared to 15 local authorities where all of their schools got the top ratings.
Brian Lightman, general secretary of the Association of School and College Leaders, said the variations are caused by different levels of deprivation.
"In some areas, there is work to be done because teachers there face greater challenges. We expect there to be variation in Ofsted judgments because of this," he said.
But Hazel Pulley, head of Parkfield Community School in Saltley, Birmingham, blames the regional differences on too much "variance" in the way Ofsted makes judgments.
"Ofsted looks at statistics about exclusion in making its judgment about behaviour. These can be well managed by schools - for instance, through managed moves to other schools or by varying children's attendance," she said.
Insight, pages 26-27.