A decline in education standards could occur as schools struggle to cover classes with specialist teachers amid recruitment and retention challenges, MPs have been told.

Schools are increasingly having to rely on cover staff and non-subject specialists to teach pupils due to teacher vacancies, education leaders have warned.

Union bosses told the Commons Education Select Committee that there is a “crisis” in teacher supply, with one leader warning there is not a school in the country which is not being affected by shortages.

Dame Alison Peacock, chief executive of the Chartered College of Teaching, told MPs on Tuesday: “We’re getting to the point where if you can’t even find a supply teacher, if there isn’t even someone that you can phone up that can come in, it gets to desperate stakes.

“Then you start to think ‘well can we have a cover supervisor that can carry that class over?’ and that then leads to a decline in standards so we’ve got a very real problem.”

She added: “I’m speaking to colleagues who are headteachers, who are senior leaders, who are saying ‘we’ve never known it this bad. We don’t know how we’re going to fill our posts’.”

It comes after Government figures this month revealed that 44,000 teachers in England left their jobs in state schools last year. This represents 9.7% of all qualified teachers – the highest rate since 2017/18.

The Department for Education (DfE) data also showed that the number of teacher vacancies doubled from 1,100 in November 2020 to 2,300 in November 2022.

Mary Bousted, general secretary of the National Education Union (NEU), told MPs that there has been a “massive rise” in cover teachers being used as a population bulge is moving into secondary schools.

“Teachers teaching out of the subject area in secondary is now happening on an industrial scale and that will get worse,” she said.

Education union leaders told MPs on Tuesday that issues with teachers’ pay and workload were contributing to recruitment and retention challenges.

It comes after the NEU announced that its teacher members in England will stage fresh strikes on July 5 and 7 in an ongoing dispute over pay.

The NEU – alongside three other education unions – are currently balloting their members in England to take action in the autumn term.

Accountability pressures on school staff and issues with pupil behaviour were also cited as drivers.

Paul Whiteman, general secretary of school leaders’ union the NAHT, said school leaders face a “cycle of psychological torture” waiting for an Ofsted inspection which affects their workload and mental health .

When asked whether pupil behaviour was driving teachers out of the classroom, Patrick Roach, general secretary of the NASUWT teaching union, said: “There is no doubt that pupil behaviour is a significant issue of concern to teachers regardless of length of experience.

“We can put to the pandemic, and what has happened subsequent to the pandemic, as having created a spike in relation to behaviour issues and challenges within schools.”

Addressing MPs on teacher shortages, Dr Roach added: “These are systemic challenges. There isn’t a school, frankly, in the country that is not impacted by the current recruitment and retention crisis.”

Julie McCulloch, director of policy at the Association of School and College Leaders (ASCL), shared school leaders’ stories with MPs to highlight the challenges they are facing.

She said one member said they are going to have to use “unqualified teachers or non-subject specialists” to teach larger classes – “even classes doubled up in the hall” – due to shortages and budget concerns.