Secondary class sizes have risen for the sixth year in a row adding on average two more pupils to every class (rising 20.1 to 22.3 since 2015).

What the headline national figures do not show is how dramatic the rise is in some areas. Great Grimsby has the largest increase in class sizes with more than six more pupils in every secondary class, 19.1 in 2010-11 to 25.4 this year; in addition, 30% of pupils of secondary pupils were in classes with more than 30 pupils per class.

Bristol East, West Suffolk, Leeds Central and Norwich South all had increases of five or more extras pupils per class.

Bassetlaw, Kingswood, Ealing, Southall, Wirral West, Nottingham East, Reading East, Barnsley East, Blackley and Broughton, Bristol West and Coventry North East all had increases of four or more extras pupils per class.

Shrewsbury and Atcham had the largest secondary classes with an average of 26.3 pupils per class which has increased from a very high 24 per class in 2010-11.

Winchester, Great Grimsby, Bridgwater and West Somerset, Sheffield South East and Brighton Pavilion had secondary classes with more than 25 pupils per class. Class sizes in all these constituencies have increased over the last ten years and all have a substantial share of pupils in classes with over 30 pupils.

Bournemouth East had the largest primary classes with 29.5 pupils in every class.

Sheffield, Hallam, Christchurch, Basildon and Billericay, Mid Dorset and North Poole, and Sutton and Cheam had primary classes with an average of 29 or more pupils. All had more than one in six pupils taught in a class with more than 30 pupils and Christchurch had more than one in three pupils in an overly large class. 41% of pupils in New Forest West were crammed into large classes.

Wolverhampton North East saw the largest rise in primary class seizes with an addition 2.8 pupils per class, taking them from 25.9 per class in 2010-11 to 28.7 in 2020-21.

Birmingham Northfield, Birmingham Hodge Hill, Burnley, Buckingham, Dudley South and Liverpool Riverside all had two or more pupils in the average primary class.