Same sex schools
© GettyPupils of all abilities are more likely to succeed if they go to single-sex state schools
Girls achieve better exam results when they are taught in single-sex schools, research has shown.

Analysis of Key Stage 2 and GCSE scores of more than 700,000 girls has revealed that those in all-female comprehensives make better progress than those who attend mixed secondaries.

The largest improvements came among those who did badly at primary school, although pupils of all abilities are more likely to succeed if they go to single-sex state schools, the study indicates.

The research by the Good Schools Guide confirms previous claims that girls benefit from being educated away from boys.

A Government-backed review in 2007 recommended that the sexes should be taught differently to maximise results, amid fears that girls tend to be pushed aside in mixed-sex classrooms.

That followed an Israeli study which suggested that when there is a big proportion of boys in a class, both boys and girls do worse academically. Results improved as the percentage of girls in a class increased.

Groups like the Girls' School Association and the Girls' Day School Trust have long claimed that they offer a better education for their pupils, but the number of state schools where boys or girls are educated separately has declined from 2,500 in the 1960s to about 400 today.

The latest research compared the results of 71,286 pupils at all-girl comprehensives to those of 647,691 girls at co-educational comprehensives.

It came as a rift developed last night over the use of elite A-level grades, with leading universities lining up to reject the new A*.

Oxford, Warwick and the London School of Economics were among 13 universities confirming they would not favour students applying after being awarded an A* in exams.

It comes despite moves by others - including Cambridge, Bristol, Imperial College London and University College London - to accept the new top grade.

Experts warned that the indecision risked causing chaos and confusion for thousands of teenagers.

The A* is being introduced for sixth-formers sitting final exams in 2010. Earlier this week, Cambridge confirmed most students would need at least one A* to get a place on undergraduate degrees.

Yesterday, The Daily Telegraph surveyed other top universities to find out how many would follow.

Bristol said admissions tutors would be free to consider the A* grade to select students. Imperial said it would be used for seven of its most prestigious subjects and UCL confirmed it would be used to dictate entry to a small number of courses.

But others insisted A* students would not be favoured until 2011 or 2012 at the earliest.

This includes Oxford, LSC, Liverpool, Durham, Newcastle, Edinburgh, Cardiff, London University's Queen Mary College, Warwick, York, Sheffield, Nottingham and Leeds.