The Big Question: Should children be taught in single-sex classrooms?

Research shows that girls feel less intimidated when boys have left the classroom

Why are we asking this now?

Because the new Schools minister, Sarah McCarthy-Fry, has called for more single-sex classes in schools, believing in particular that girls would learn from being taught science in single-sex classes – even in co-educational schools.

Why does she want this?

She believes that girls can feel intimidated in mixed classes because boys put their hands up and answer all the questions. Figures do tend to back her theory that fewer girls opt for science – possibly as a result of careers advice or a feeling that science is a boys' subject. The number of boys taking physics at A-level this summer was just over 21,000 while slightly more than 6,000 girls took the subject.

Is there any basisfor this belief?

Research conducted by the University of Cambridge would appear to support Mrs McCarthy-Fry. In a study published just three years ago, girls spoke of being more relaxed when removed from "social pressures" once boys were absent from the classroom. Typical of the comments they made were: "You don't need to act as though you're really cool, especially when you're not feeling as though you are!" and, "You feel braver and less embarrassed in offering answers, because there are no boys to make fun of you when you are wrong."

There is alternative evidence to consider. Research by the Centre for Longitudinal Studies at London University's Institute of Education shows that boys who have been to single-sex schools are more likely to end up divorced (37 per cent of those going to boys' only comprehensives compared with 28 per cent from co-educational schools). "There does seem to be a picture of boys from single-sex schools finding it more difficult to sustain a relationship with the opposite sex."

Do Mrs McCarthy-Fry's comments resonate beyond science lessons?

Supporters of single-sex education would argue that they do. Some state schools, notably Shenfield comprehensive in Essex, have experimented with introducing single-sex classes for a variety of lessons. Maths is another example where girls are said to benefit from being taught in singlesex classes. International figures show that – while girls are ahead in all countries in reading by the age of 15 – they lag behind in 38 out of 40 countries in maths. As a result, it is argued, they are less likely to opt for it at A-level – particularly if they are in a co-educational school.

The exam league tables would tend to support the theory that both boys and girls do better in single-sex schools – as they dominate the top of the performance tables and have done so for years. But it is also true that all the leading performers are selective and that there are more selective single-sex schools than comprehensives – so this may be the reason for their success.

So can conclusions be drawn?

Research is inconclusive as to whether pupils do better in single-sex schools. Professor Alan Smithers, the respected researcher from the University of Buckingham, argues that it makes little difference to a youngster's academic performance whether their parents have sent them to a co-educational or single-sex school. "No consistent findings have been obtained in relation to performance, attitude or teachers' actions," he said. "This is perhaps not unexpected since trying to tease out the effects of individual classes among all the other influence is even more difficult than comparing schools."

What might be the impact of the minister's comments?

At the very least she has renewed the debate over whether girls' schools are better for girls than co-educational ones. They also follow on from what Vicky Tuck, the president of the Girls' School Association and principal of Cheltenham Ladies' College, said at her association's annual conference last week – that the pendulum was swinging back in favour of single-sex education. Mrs Tuck said there was incontrovertible evidence to suggest that girls learnt differently to boys because of "neurological differences" in the development of the brain.

Research showed that girls warmed more to the modular approach adopted in GCSE and A-level exams whereas boys preferred to save their efforts for one-off end-of-year examinations. Further research has also suggested that improving reading performance in schools is more likely to be attained by offering boys and girls different books – which could only really be done if they were taught separately. Boys prefer action books while girls are happier with traditional classics from authors such as Jane Austen which dominate the book lists set out for the national curriculum.

Can single-sex classes be made compulsory?

The short answer to that is no. Mrs McCarthy-Fry has no powers to insist on either – although the very fact that the debate has been opened up again after four decades in which the number of single-sex state secondary schools has slumped from 2,500 to just 400 might persuade providers of the need for more single-sex schools. With the advent of the academies programmes, private sponsors are coming forward with their own proposals to sponsor state-financed independent schools.

In addition, the Conservatives have said they would adopt the Swedish voucher system – whereby parents are given a voucher to purchase a place for their child at any school they choose. This has led to the establishment of a new breed of independent "free" schools – some single sex. So far, there have not been any proposals for single-sex academies but the emphasis on parental choice could see that change.

A lot, though, may depend on how assiduously the debate is followed up from here. In other words, the ball is in the minister's court as to how she chooses to pursue this debate. An interesting question would be where does her boss, the Children's Secretary, Ed Balls, stand on the issue.

What about single-sex classes for boys?

The fervour is not quite the same. All the evidence points to the fact that, while single-sex education is popular for girls, the reverse is true for boys. Witness what has been happening to the Headmasters' and Headmistresses' Conference, the organisation which represents what were traditionally known as the 250 most elite boys' schools in the country – such as Westminster, Marlborough and Wellington.

The majority of them now admit girls – at least into the sixth form. As a result, the number of single-sex state schools has fallen by at least 130 in recent years. Some people believe that this has only happened because girls outperform boys in almost every subject at GCSE and A-level – so admitting them is bound to improve a school's performance in exam league tables.

So what will happen next?

Internationally, there has been a return to more single-sex schooling – the number of girls-only schools in the United States has risen by 40 per cent in the decade up to 2006. In the past, the trend of provision in countries such as the United States has been replicated in the UK.

So is single-sex education the answer?

Yes...

* Research shows that girls feel less intimidated when boys have left the classroom

* A glance at the exam league tables reveals the top places are taken by single-sex schools

* The take-up of subjects such as science and maths by girls at A-level is better in single-sex schools

No...

* There is no conclusive research to prove that girls do better when taught on their own

* The dominant single-sex schools are selective. That may be the real reason for their success

* Pupils fail to develop relationships with the opposite sex if they are taught in a single-sex environment