The director of A-levels at one north-west sixth form and a Midlands head are among those who claim exams are no longer as challenging as they used to be, says a new survey.
According to the study by political think-tank Civitas, 100 per cent of teachers think the rise in A-grades at sixth-form level is not an indication today's students are more able.
Eight in ten of those surveyed said they believe they would have achieved higher grades if they were to sit their exams today.
Anastasia de Waal, director of family and education at Civitas and author of the report, said: "That the majority of teachers think they would have achieved higher grades today strongly suggests that it is easier to do well today."
Responses to the survey included that of a north-west director of A-levels who said: "The A-level is not aimed at the same people as it was 30 years ago: a larger cohort must have easier exams or too many would fail."
One Midlands headteacher described the exam system as a "shambles" and complained of low standards among candidates.
The news follows comments made last week by one London head, who branded the GCSE curriculum as "boring".
Written by Charlotte Michaels