GCSE pupils across the UK have had more than 75 million lessons taught by non-specialist teachers in the last two years, according to research carried out by the Liberal Democrats.
The findings show that the average GCSE pupil will have had one in 10 lessons with a teacher who does not specialise in the subject they are teaching.
Some subjects are particularly affected by this, with 12.2 per cent of maths lessons and 19.9 per cent of modern language lessons being taught by non-specialists.
For a teacher to be classed as a ‘specialist’ to teach a GCSE subject, they have to have achieved at least an A-level or higher qualification in that subject.