Ben Goldacre's analysis of examination pass rates and grades (Bad Science: Mystery of the A-level, 21 August) is to be welcomed, and he quite rightly considers a range of reasons for the increase in success rates. One significant factor, however, is not mentioned. In the 60s, 70s and 80s, grades were allocated by norm referencing, which ensured that every year the same percentage of candidates received grades A, B etc. This had the advantage of eliminating variations in the difficulty of individual questions and of whole papers, as it didn't matter whether one year's exam was harder or easier than the year before, since the same percentage of candidates attained each grade. However, it did not take into account variations in the overall quality of each year's candidate cohort; a "good" cohort would receive the same percentage of top grades as a "poor" cohort.
Over the past 20 years or so, in contrast, GCSEs and A-levels have moved away from norm referencing to criterion referencing, whereby each grade is allocated according to whether a candidate has demonstrated the knowledge and skills required for that grade. If you can satisfy the requirements, therefore, you get the grade – a bit like taking a driving test, which doesn't seem to be criticised as getting easier, in spite of increased numbers of people passing.
The high-stakes nature of public examinations for students, teachers and schools, and the publication of specimen answers by exam boards, means that teachers and students have a strong incentive to train for success, while understanding much more clearly what is needed to achieve top grades. Under these circumstances, it would be a matter of concern if grades had failed to improve. As it is, teachers and students should be congratulated for gaining such positive outcomes from the situation they have been placed in.
Dr KJ Eames
• Ben Goldacre calls for more research into the comparability of exam grades over time. In fact a great deal of research has been carried out, notably by the examination groups themselves. I would recommend a recent comprehensive summary and discussion that is available in a book published by the Qualifications and Curriculum Authority in 2008, entitled Techniques for Monitoring the Comparability of Examination Standards. The editors warn against simplistic comparisons of pass rates and shock headlines. They point out that: "This is not an enterprise characterised by straightforward solutions to problems."
The questions raised by Goldacre are all addressed by this volume and the current state of the research evidence is clearly laid out. It should be required reading for all those in the media who wish to commentate on the issue.
Professor of social statistics, University of Bristol
• The notion of a "mancession" (Learning new ropes, 19 August) is a red herring. Male unemployment rose faster during the recession, but as women are more than twice as likely to work in the public sector as men they are particularly vulnerable to job losses in the coming years. Julia Margo goes on to highlight boys' struggle to compete in today's female-friendly exams and suggests apprenticeships as a route to tackle this "crisis of masculinity". But the classroom to workplace crisis affects women as well as men. Girls have outperformed boys at school for many years now, but this advantage has not translated into the labour market, where the full-time pay gap is 16%. Female apprentices – earning 21% less than male counterparts – share a similar fate.
Helping today's youngsters turn their record breaking A-level results into labour market success, irrespective of gender, would go a long way to tackling all of these crises.
Deputy general secretary, TUC
• Having recently retired from many years teaching A-levels in state schools and sixth-form colleges I am not one bit surprised that the independent sector nabbed most of the A*s (Comprehensives lose out to elite schools in race for coveted A*, 20 August). State sixth-form classes are made up of a rich mix of students in terms of their academic ability, social and ethnic background. This creates dynamic groups that are a pleasure to teach, despite some of the challenges that emerge. After two years one can often see diverse friendship groups emerging that will remain intact for many years. Many walk away with top grades, others are more than happy with so-called mediocre grades that will get them on to some excellent courses, while yet others are able to find good jobs. The national and media obsession with academic greenhouses and socially exclusive networks is frightening and deeply depressing.
• I was shocked to see that teachers in state schools were accusing thousands of university admissions officers of being part of a conspiracy to use a secret list of "banned" A-level subjects to enable the most prestigious universities to accept more private school pupils (Top universities secretly list 'banned' A-levels – teachers, 21 August). Are these the same liberal admissions officers who are regularly denounced by private school teachers for using preferential A-level offers to enable the most prestigious universities to accept more state school pupils?
Professor SH Rigby
University of Manchester
• On page 1 you describe teachers' suspicions that the Russell Group universities reject outright pupils who take A-level subjects such as law, art and design, business studies and drama. On page 40, you tell us that "Durham University is to offer a Harry Potter course as part of its education degree". I take it that Durham is not part of the Russell Group.