Nearly 1 million primary children, more than a quarter of the total, are in classes of more than 30 with one teacher and the figure has gone up by 83,000 during the past year, according to figures yesterday.
The percentage of children in classes of more than 30 varies from 55.9 per cent in Kingston upon Thames, south-west London, to 3.3 per cent in Kensington and Chelsea in central London.
Figures obtained from the Department for Education by Stephen Byers, Labour MP for Wallsend, show that the authorities with most children in classes of more than 30 are Kingston, Redbridge (55.1 per cent) in north-east London, and Trafford (49.1), Tameside (47.4) and Rochdale (47.2) in Greater Manchester. The five local authorities with the smallest class sizes are Kensington, Haringey (3.8) in north London, Tower Hamlets (4.6) in east London, Lambeth (4.8) in south London and Hackney (5) in east London.
Mr Byers said: 'If a teacher is facing a class of over 30 10-year-olds it becomes a question of crowd control rather than a valuable learning experience. The Government appears totally indifferent over the issue of ever-increasing class size - this is in total contrast to the view taken by parents who regard reduction in class size as a top priority.'
The Department for Education said: 'The Government recognises that class sizes have increased slightly but there is no clear relationship between class sizes and the quality of education.' However, recent work in the United States suggests that small classes improve the youngest children's learning.