Figures were recently released by education consultancy SchoolDash showing that girls in single-sex schools got better results at GCSE level than those who attended mixed-sex schools.
Girls’ schools in London did particularly well in comparison to co-educational schools. 
Of course, there are many factors at play: lots of girls’ schools are grammar schools, they tend to have long-standing permanent teaching staff, rather than rely on supply teachers and girls’ schools can be favourites amongst more conservative and perhaps more involved parents. However, those issues all apply equally to boy’s schools and they tend to have nowhere near as significant an advantage over mixed-sex schools. So what’s going on?
Studies have shown that teachers’ unconscious bias leads to girls and boys being encouraged or discouraged in particular subjects. For example, recent experiments have shown that teachers mark girls lower than boys in maths when their genders are known, compared to ‘gender-blind’ marking. This has led to calls for teachers to be better trained to combat this bias.
Unconscious bias matters because what teachers think deeply affects the choices that kids make. When girls feel that they are ‘not very good’ at maths and science they tend to pass over these subjects, the very subjects that could result in better jobs with higher pay, when choosing their academic journeys. All-girls schools eliminate this problem.
A few weeks ago, Richard Cairns, Head of Brighton College, waded into the debate by saying that girls at single-sex schools might leave with great exam results but “if they cannot meaningfully converse and communicate with male colleagues, they will be at a huge disadvantage”.
This leads me to wonder what this special way of meaningfully communicating is, since I thought that the general idea was to get good at communicating with people and most of the world is trying to move away from the idea that you talk to a male colleague in one way and a female colleague in a different (often less respectful way). I really want to know what this special way of talking with male colleagues is: does it involve football or other clichés for example?
I have a natural aversion to segregation but when it comes to girls’ schools I’m a supporter. Evidence shows that girls leave more, not less, prepared for further study or work in a broader range of disciplines, more confident and ambitious. Hopefully, one day, there won’t be a need to have single-sex schools but whilst girls are subject to unconscious bias and gender stereotyping the need is real and present.