Yes: John Welsh, Headteacher, Bexley Grammar School

We are a grammar school in a South London suburb and take the top 25 per cent of students in terms of ability — we're not super selective. Our students are bright, but they're typical.

With our brightest students, we find there is quite a gap between GCSEs and A levels, or the International Baccalaureate (IB), which we offer. If students want to go on to university to study science, for example, we find that GCSEs don't stretch them enough and don't develop the skills necessary for a university degree.

We are looking for something with a little bit more rigour and the international GCSE (iGCSE) seems to have that. They were developed from the old O levels and command greater attention to detail. They are more technical and academic than normal GCSEs. At the moment you can take iGCSEs abroad and in independent schools. Lots of independent schools are putting their students in for iGCSE courses and other alternatives to GCSEs such as the Middle Years Programme, which leads to the IB.

GCSE science in particular is not demanding enough for our brightest students. I believe that there's been an attempt to make the GCSE science course more accessible for a broader range of students. In doing so, it has removed some of the detail and made it less academic. This has made it more difficult to jump from that to A level. The Government should revisit the science GCSE syllabus and assess its suitability for the full range of abilities. I understand that they are trying to make science appeal to a wider audience. However, the problem is that it doesn't develop academic rigour. It's not going to develop scientists, but only people who are aware of the general principles of science.

Other subjects don't have such a wide gulf between GCSE and A level. In maths, there are qualifications you can take to supplement the GCSEs. Some of our students will take Additional Maths. Really, though, GCSEs should be stretching enough for all students. The exams need to be looked at with regard to the full spread of ability. It seems to me that it's the most able students who are not being given the proper academic diet — not enough challenge, content or depth of understanding. We want to run the iGCSEs, but we have been told by the Education Secretary that because we are a state school we're not allowed, as they are not accredited by the Qualifications and Curriculum Authority.

I hope that the Goverment will approve iGCSEs so that we can offer the same advantages and courses as independent schools. I fear that if state school students are not offered more stretching courses, they are going to find it more difficult to compete with students from the independent sector. I believe they will go on to take their A levels from a better basis and thus gain the highest grades and the best university places. The danger is we will end up with a two-tier system.

No: John Dunford, General secretary, the Association of School and College Leaders

The purpose of the GCSE is, and always has been, to provide an examination for the whole ability range, replacing the separate O level and CSE examinations. We must not return to educational apartheid at age 16, or the needs of modern society will not be served. So GCSE papers have to be set in a way that provides a challenge for the most able students who aim to obtain a top grade, while being accessible for young people of lower academic ability who must have the opportunity to demonstrate their knowledge and skills without being put off by inaccessible questions.

The criticism of the GCSE that it does not stretch the brightest pupils is aiming at the wrong target. Good teachers do not regard an exam syllabus as a limitation on the education of their pupils. Teachers of bright pupils have always gone beyond the syllabus to stretch the intellect of their pupils.

Good English teachers will introduce the brightest pupils to a wider range of texts, good maths teachers will explore more abstract concepts, good geography teachers will bring into their lessons parts of the world that are not on the syllabus, and good history teachers will encourage bright students to read widely and gain greater depth in their understanding of historical interpretation.

The ages of 14 and 15, when children generally do GCSE courses, is exactly the right age to stimulate their intellects in this way. Good teachers help them to achieve top grades, but they must also bring to them the excitement of learning and it is expecting too much of any syllabus that it should do this for all students. The International GCSE (iGCSE) certainly won't.

It is not true, either, that the GCSE examinations are getting easier. I understand that there is a fear that the modular approach to GCSE assessment will lead to a “bite-sized chunks” approach on the part of pupils. But this is not a foregone conclusion; rather, it is one that depends on the way in which the teacher approaches the subject.

To create a situation in which independent schools do one kind of exam and state schools do another would be extremely damaging to the education service as a whole. The iGCSE is a throwback to an earlier era and it is backward to move in that direction. It is an O level-type paper, and its syllabus and examination style will not necessarily be more challenging than the GCSE, even in the hands of good teachers. I think there is a false optimism around the idea of the iGCSE and the Middle Years Programme of the International Baccalaureate, which Anthony Seldon, the Master of Wellington College, favours.

It would be far better if independent schools worked within the system to improve the GCSE. What I would like to see these schools do is join the debate from the inside, rather than the outside. The whole education sector — independent and state-funded - must come together to discuss what's next for the GCSE examination.

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