The rise of the International GCSE is being heralded as a return to old-fashioned standards of assessment, when teenagers swotted for rigorous examinations, coursework had not been invented and the word modular was meaningless.

But the O-level style IGCSE could end up heading a drift into educational segregation. Currently, school-leavers can make their way in life without their choice of qualification betraying their background. Most still take GCSEs, then A levels.

The exam system is fragmenting: independent and grammar schools increasingly favour the IGCSE because it is thought to be more challenging. Teenagers take the exams after two years of study.

Most state schools have no choice but to stick with the GCSE, which will undergo sweeping reforms next month to make it more modular. Students will take “bite-sized” chunks and will be assessed after each unit.

Traditionalists are expected to seize on this as further evidence of the dumbing-down of GCSEs. Passes have risen every year since the exam was introduced in 1988. Some head teachers complain that the qualification has become pointless because so many pupils achieve top grades, despite the introduction of the A* in 1994.

The examination boards believe that rote-learning large amounts of information is outdated and less relevant to the skills required in today’s job market.

Breaking up GCSEs will allow greater flexibility, with bright, young pupils taking modules early, they say.

Such divergent approaches are likely to result in qualifications becoming an instant giveaway as to how much – if anything – parents have spent on their child’s education.

It is improbable that the Government will be swayed in the near future by the IGCSE’s growing popularity.

Jim Knight, the Schools Minister, said recently that the qualification was in “no way superior to the GCSE” as it was aimed at international students and did not focus on “English cultural or historical concepts”.

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