More pupils will gain top A* grades in English and maths A levels this year, according to a leading assessment academic.

Professor Alan Smithers, said the long-term decline in the number of English A-level entries, alongside a more recent downturn in the number of pupils taking A-level maths, meant both subjects would have smaller, higher-ability cohorts this year.

And that would result in a higher proportion of candidates achieving the top A* grades.

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Professor Smithers, director of the Centre for Education and Employment Research at Buckingham University, said that in both A-level English and maths, lower-ability candidates would have “selected themselves out” after finding the revised GCSEs too challenging.

The 2019 A-level cohort was the first to take the revised GCSE English and maths exams in 2017.

In a report on A-level trends, Professor Smithers writes: “Entries in all the English and maths papers have gone down. If the experience of tougher GCSEs and the prospect of tougher A levels have led to potentially weaker candidates opting out, then the percentages of top grades could be expected to rise and be reflected in the overall grade distribution.”

The report emphasises the potential for a higher proportion of top grades in A-level maths, as maths and further maths contributed to a third (31.4 per cent) of A* grades awarded across all subjects in 2018, while maths alone contributed to 24 per cent of these grades.

A levels in English language and English language and literature were among the subjects that awarded the lowest grades in 2018, the report says.

“It follows that, if indeed the reduction in entries means fewer weaker candidates, then the percentage of top grades will go up.”

In English, entries to all three qualifications fell in 2019 according to provisional figures from Ofqual. In 2018 67,865 pupils were entered for English A-level qualifications, while in 2019 the number of entries fell to under 59,000.

In maths qualifications, the total number of entries in 2019 fell by over 6,000 entries (6 per cent), from 106,405 in 2018 to 100,105 this year.

“Provisional figures from Ofqual show that entries to both English and maths fell in 2019, perhaps because the experience of the tougher GCSEs and the prospect of harder A levels put potentially weaker candidates off,” the report says.

However, Professor Smithers predicted that the overall proportion of top grades across subjects would remain consistent, citing Ofqual’s use of comparable outcomes.