The number of children in England being taught in classes with 31 or more students has surged over the past decade, analysis suggests.

As millions of children return to class this week, Labour said it found the proportion of secondary students in classes of at least 31 has increased from one in 10 in 2010 to almost one in seven.

It suggests that the number of primary school pupils in classes of 31 or more has also increased from one in nine in 2010 to one in eight pupils.

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Labour is warning that larger class sizes could create challenges for teachers trying to give pupils individual support and attention as they return to school.

Progress in reducing class sizes ‘reversed’

Labour’s shadow education secretary, Kate Green, said: “The Conservatives have turned back the clock on education, reversing 20 years of progress to reduce class sizes and ensure every child gets the dedicated teacher attention they need.

“Under the Conservatives, the gap in learning between disadvantaged pupils and their peers had not narrowed for five years even before the pandemic. These Conservative choices are holding back children’s education.”

The analysis, of figures from the House of Commons Library, suggests that the number of secondary students in classes of 31 or more increased by more than 130,000 between 2016 and 2020 - a rise of 43 per cent.

The number of primary school pupils in classes of 31 or more has increased by nearly 20,000, or 3.7 per cent.

And statistics from the Department for Education, published in June last year, showed that the number of students in state secondary schools in England had risen by 81,300 to 3.41 million.

Meanwhile, education unions say insufficient funding, as well as a shortfall of places, has caused class sizes to rise.

Geoff Barton, general secretary of the Association of School and College Leaders, said: “The reason that the number of children in large classes has risen is simple - lack of money.

“Over the past five years, the number of children in our schools has increased and government funding has been insufficient. The result is that there are fewer teachers and more children.”

He added: “Schools have worked very hard to ensure that funding pressures do not impact on the education of children, but it is obviously the case that larger classes make it more difficult to give struggling students individual support and attention.

“Sufficient funding is a vital part of improving the outcomes of pupils who face the greatest challenges.”

Mary Bousted, joint general secretary of the NEU teaching union, said: “Clearly, with such large numbers in any one class, teachers and support staff have a far harder job in ensuring every child gets the attention they need.

“Much of this problem has been caused by government’s failure to address the shortfall in school places that has been an issue for many years.

“The lack of sufficient school and college funding has exacerbated this problem, with many schools having to cut the number of staff to balance the books.

“Government needs to address this problem to ensure every child gets the best education they possibly can. Having a teacher and support staff dividing themselves between 30-plus children is not acceptable.”

A Department for Education spokesperson said: “Average secondary class sizes remain low, at only 22 pupils, while the average primary class has remained stable at 27 pupils., This is despite an increase of almost 800,000 pupils since 2010 which is more than ever before.

“Last year most pupils were offered a place at one of their top three choices of secondary school, while between 2010 to 2019 we created one million additional school places overall, with many more in the pipeline.”