Secondary schools in England have seen bigger classes for students after a cash crisis has forced headteachers to cut staff numbers by 15,000, official figures reveal.

That equates to an average of five members of staff for each secondary school since 2015.

Now teacher unions say that staff numbers have fallen between 2014 and 2017 by 15,000 while an extra 4,500 pupils entered the school system in that period.

Union leaders are warning that a £2.8 billion reduction in school funds is leaving headteachers with little choice but to reduce teacher numbers.

Research has revealed that there are, on average, 1.6 fewer teaching assistants in each secondary school and 2.4 fewer classroom teachers. There are also 1.5 fewer support staff available.

School budgets are now at a ‘breaking point’

The figures have been provided by the National Association of Head Teachers and its general secretary, Paul Whiteman, warns that school budgets are now at a “breaking point”.

He says: “It’s impossible now for schools to avoid making redundancies after school leaders have made other efficiencies and to continue keeping class sizes at acceptable levels and offering a rounded full curriculum to their pupils.”

Mr Whiteman said that the “school funding crisis is real”.

His views have been echoed by the National Education Union’s joint general secretary, Dr Mary Boustead. She says that education cuts are now “damaging children’s education”.

‘The pupil to teacher ratio is getting worse’

Dr Bousted added: “The pupil to teacher ratio is getting worse and schools have cut back on teacher numbers. Children have one chance when going to school and we should invest in this generation who will see profound changes during their lives.”

After education became a key General Election issue, the government put together a £1.3 billion plan to help support England’s schools.

However, while school spending has been maintained, headteachers are facing other cost issues including rising National Insurance and pension contributions which, when coupled with inflation, has led to a £3 billion real terms cut.

Now teaching experts are predicting that the spending situation may get worse with primary schools also suffering a reduction in real terms funding.

In addition, around half of the largest multi-academy chains have also issued warnings over their funding problems.

Biggest education cuts and issues over classes

The teaching unions highlight that the biggest education cuts and issues over classes have been seen in areas that also feature the lowest average funding per pupil which include York, the Isle of Wight, Derby, Central Bedfordshire and Milton Keynes.

The government has introduced a new funding formula aimed at distributing money fairly across the education sector but this is unlikely to solve the current problems without any further major investment.

In addition to teaching unions, Unison says that the cuts to budgets have also had a big impact on teaching assistants with one person for 67 secondary pupils now being employed.

The union’s head of education, Jon Richards, said: “Children with disabilities and special educational needs rely on teaching assistants so they will suffer the most because of staff cuts.”