For instance, all 14 inner London education authorities had less than 20 per cent of their seven to 11-year-olds in large classes compared with only five other authorities across the country.
In outer London the position was more mixed, including two boroughs which packed more than 61 per cent of their pupils into classes of 31 or more. In these boroughs the percentage of oversize KS1 classes was also well above the national average.
Overall, however, only six London authorities exceeded the national average of 38 per cent of pupils in classes of 31 or more at KS2.
Outside London, nearly one in five authorities had more than half of their pupils in large classes at KS2.
Two regions stood ou as having a disproportionate number of pupils in classes of 31 or more; the North-west and the South-west. Between them, they contained nearly half of the LEAs with more than 50 per cent of their KS2 pupils in oversized classes.
In the South-west, the counties of Cornwall, Dorset and Somerset had more than half of their pupils in large classes, as did Bournemouth and Torbay.
The latter two are among a list of LEAs with above average numbers of pupils in large classes which also have selective secondary schooling. This raises a question as to whether the distribution of large KS2 classes in authorities with such schools is evenly spread across all their primary schools.
If not parents will need to be reassured that large classes do not affect their children's chances of passing any selection test.
John Howson is a visiting professor at Oxford Brookes University. E-mail: firstname.lastname@example.org.
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