Almost 100,000 children between the ages of five are seven are now in super-sized classrooms that exceed the legal limit of 30 pupils.
The Department for Education revealed that more than one in 20 children in England – almost six per cent – are being taught in large classes, despite concerns it leaves children starved of teachers' attention in the vital early years.
It also emerged that the number of 'titan' primaries – schools with at least 800 pupils – has surged to 77 in the last 12 months. The disclosure comes amid a rise in demand for primary school places, fuelled by an increase in the birth rate and the effects of immigration in some areas.
According to today's figures, an average of 27.4 infants now share the average lesson in state-funded primary schools, representing an additional two pupils in every class compared with 2007.
It emerged that 93,345 of the youngest primary school pupils – 5.9 per cent – were in large classes.
It represents a rise of more than 20,000 in a year and a four-fold increase on the 23,210 pupils in the biggest lessons in 2007. Of those lessons exceeding the limit, the vast majority were classed as 'lawful', meaning schools sought local authority permission before taking on additional pupils.
But figures show the number of 'unlawful large classes' has more than doubled, with 17,270 pupils in these lessons compared with just 7,125 a year earlier.
Department of Education officials said the increase was larger than in previous years and had been driven by a 2.5 per cent rise in the number of primary school pupils, offset by a 0.9 per cent fall in the secondary population.
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