When Cranbrook School announced its move away from an all-boys environment into coeducation, it tapped straight into a debate plenty of Sydney families know well: does school gender mix make a difference?

First up, the big picture: there isn’t a clear academic winner. Major reviews summing up hundreds of studies — including research with more than 1.6 million students globally — find little to no difference in academic outcomes between co-ed and single-sex schools once you control for background factors like socio-economic status and teaching quality. Meaning boys and girls often do just as well regardless of school type. But look closer at Australian data and you’ll see patterns people cite. Exclusive analyses of the 2025 national NAPLAN results showed that single-sex schools, though only about 7 % of enrolments nationally, take a disproportionate number of spots in the top academic rankings. Forty-two of the top-performing schools are single-sex institutions.

Some specific subject-level trends show up too: girls from girls-only settings have historically been more likely to take advanced STEM subjects such as higher maths and chemistry compared with co-ed peers. Socially and culturally, co-ed schooling is argued to build everyday communication and empathy across genders — practical skills for uni, workplaces, relationships and life in Sydney and beyond.

So is co-ed “better”? Not necessarily. But the real world of friendships, mixed workplaces and social networks isn’t single-sex — and that’s exactly what co-ed high school is preparing students for.

Whether it’s academic results or life skills, the best choice always comes back to the individual student — not if the uniform is M or F.

Benjamin Tay