While there are no reliable counts of single-gender schools in the first half of the 20th century, best estimates are that most were schools for white boys. Many of the girls' schools that did exist early on served as "finishing" schools rather than preparation for college. In the 1960s and 1970s, the civil rights and feminist movements combined their equality crusade fervor to "open" previously exclusive men's schools to women, and white schools to blacks. Once single-sex schools were knocked out of the ring, the gender fights occurred almost exclusively inside the coed arena. Great efforts were made to make schools more girl-friendly--introducing new math and science curricula and teaching methods, for example--which seemed to succeed only in creating a "boys crisis." Initial efforts to revive single-gender public education were done in by "conventional values," buttressed by what was then a sturdy Title IX ethos. The resurgence of single-sex schooling has also been the result of hard-fought battles to recapture the benefits of difference and take advantage of educational choice. The rewriting of Title IX addressed confusion created by the restrictions in the original 1972 statute and the support for single-sex education in the No Child Left Behind Act of 2001. But the dire predictions about the resegregation of public schools and turning back the clock on civil rights gains for women never materialized. While various groups threatened legal actions, none have materialized. It is a new world, especially for women, and serious educators seem to realize that single-sex schools and classrooms are not a threat, but another arrow in the quiver of education quality. (Contains 1 figure.)