A report by the Association of Teachers and Lecturers has accused schools of teaching 'on the cheap' by using unqualified staff to give lessons.
A survey undertaken by the teaching organisation found that teaching assistants and cover supervisors are being used in schools on a regular basis.
The union questioned more than 1,435 support staff, and found a quarter (25.4 per cent) of the teaching assistants and almost half (49 per cent) of higher level teaching assistants said they are asked to cover lessons. Around 96 per cent of cover supervisors said the same.
Many put-upon classroom assistants criticised schools for making them do teachers' work for less pay, calling it 'teaching on the cheap'.
The general-secretary of the ATL, Dr Mary Bousted, said the cost-cutting measures were to the detriment of students.
"Schools sell pupils short by using them when the teacher is unavailable," she said. "They are used as a cheap option. It is grossly unfair on them and pupils."
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