You are correct in asserting that private and state school pupils sitting different exams is a policy disaster (Editorial, 26 August). I am no defender of the independent school system, but for once this is not of their doing.

Back when Michael Gove wanted to toughen up the exams, he approached Cambridge International because he liked the look of its exams.

He was allowed access to all its syllabuses and exams as a basis for reforming the IGCSEs. In return, candidates in state schools would be allowed to sit the IGCSE.

In the qualification I was involved with, there was no coursework, which was appealing to teachers bogged down with the continuous-assessment regime. The format of the exam was straightforward and sufficiently demanding to inspire pupils to learn. The entry suddenly ballooned tenfold.

Once Gove had got his new GCSE in place, he suddenly ordained that the IGCSE would not count towards league tables. This was a calculated move to wipe out the competition to his new GCSE, as no state school could afford to appear to be at the bottom of the league tables. They withdrew from the IGCSE.

The independent schools, however, don’t even pay lip service to the league tables and were unwilling to move from a qualification they were happy with to one that was an unknown quantity and likely to experience teething problems.

Cambridge International has a considerable number of candidates from all over the world. The IGCSE is a prestigious qualification with international recognition: its grades are aligned with international standards. I would challenge the assumption that it is “easier” – having to award a “pass” at 31% suggests that there is something wrong with the GCSE exam. GCSE candidates in our state system are being shortchanged indeed.

Name and address supplied

• Your argument that the domestic GCSE is harder than the IGCSE is wrong. The specification may be broader (the current Edexcel IGCSE chemistry has 15 pages of content compared with AQA’s 66 pages) but the grade boundaries this summer are accordingly lower. The AQA combined-science GCSE required only 64% for the top grade and 21% to pass; the Edexcel IGCSE was 72% and 39% respectively.

I understand that universities are only interested in students’ GCSE results to see if their predicted A-levels grades are accurate. Public schools are mostly interested in getting students to their first-choice university, so choose a qualification that meets their needs for A-levels.

As far as I can see as head of chemistry, the domestic GCSE contains a lot of content that cannot be examined in any depth and will not be touched on at all at A-level. If we were to turn away from IGCSE to the domestic GCSE it would mostly be to ensure our students were not treated differently when applying to university due to social or media pressure as regards the quality of their IGSCEs.

Ewan Drysdale

Kimbolton school, Huntingdon, Cambridgeshire

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