Are sex-segregated schools and classrooms an antidote to gender inequities of do they reinforce sex-based stereotypes and make the gender gap worse?
We actually do not know and everything on the subject will suggest more longitudinal research be done, but for now, it looks like girls graduating from single-sex high schools are doing better than girls coming from coeducational high schools, at least at the point when they enter college.
Here are the key findings. Women graduates of single-sex private schools:
are more academically engaged (measured by time spent doing homework, studying with other students, tutoring other students, and talking with teachers outside of class);
tend to get higher SAT composite scores (verbal + math);
are slightly more likely than those who attended coed private schools to say they intend to go one to graduate school;
tend to exhibit slightly higher levels of academic self-confidence, particularly related to writing and public speaking;
arrive at college with greater confidence in their mathematical and computer abilities;
are more likely to plan to become engineers;
are more likely to intend to become involved in school clubs and student groups; and
are more likely to discuss politics.
These results seem pretty clear to me, and are stronger because the data compares women graduates from same-sex and coed private schools, getting rid of the noise related to the background characteristics.