Why More Single-Sex High Schools in Seoul Are Going Co-Ed

It’s no longer surprising that women now make up the majority in many graduate programs like law schools. But a similar trend is drawing attention at the high school level in South Korea: a growing number of all-boys and all-girls schools are transitioning to co-educational institutions — and the underlying reason comes down to academic performance.

In one notable case, a co-ed high school assigned library seats based on grades, and only about one in ten of the top students were boys. This pattern isn't unusual. It’s become almost a truism that male students tend to fill the bottom ranks when it comes to internal school performance in co-ed environments. For parents of boys, this concern is real enough to make them actively avoid sending their sons to co-ed schools.

Some families even choose elementary schools based on which middle schools will feed into all-boys high schools. In certain districts, you can see a noticeable rise in the ratio of boys as students progress from lower to upper grades — a result of parents gaming the system to keep their sons in male-dominated academic settings.

So perhaps the issue isn’t with co-ed schools themselves, but rather with the academic struggles of boys.

There are several commonly cited reasons why boys underperform compared to girls, and topping the list is — unsurprisingly — gaming. While girls do play games too, there’s a clear difference in how much they get immersed and what kinds of games they play. For many boys, it’s not just a casual pastime; strategy games and achievement-based gaming become time-consuming traps that hurt their focus on academics.

Sports can also play a role. Let’s be honest: it’s more often sons, not daughters, who stay up to watch World Cup matches. In fact, during World Cup years, it's almost a given that the number of male repeat test-takers (those taking university entrance exams again) will spike. Some parents are already worried about how the 2027 World Cup might impact their sons’ college prospects.

Romantic relationships are another factor. While dating doesn’t seem to affect girls’ academic performance as much — they’re usually able to balance both and bounce back quickly after breakups — boys often find it more disruptive. For them, a breakup can derail focus and motivation for a long time.

Interestingly, among the schools transitioning to co-education, there are more all-girls schools making the change than all-boys schools. Boys (and their parents) tend to prefer all-boys schools, while girls — with a few elite exceptions like Ewha Girls' High School — often avoid all-girls schools. Here too, academic performance may be part of the reason.

In 2025, five high schools that made the switch to co-ed were previously all-girls schools. Over the past 25 years, 85 all-girls high schools have disappeared across the country, compared to 51 all-boys schools.

Government data also shows that girls now outperform boys in basic academic skills across all subjects — even in math. The long-standing belief that boys are naturally better at math seems increasingly outdated. This isn’t just a Korean phenomenon. In countries like Norway, some educators have proposed allowing boys to start elementary school a year later than girls — to account for the growing academic gender gap.

The effects of this performance divide extend well beyond high school. It can be seen in admission rates to law school, med school, and other professional graduate programs. The question now is: Will this lead to more opportunities for women, or will we start seeing hidden social advantages quietly being introduced to support men?

Either way, it’s a shift worth watching.