Students at Claremont Academy in Chicago and their scores have become a proof point in a broadening argument between adults and institutions over whether single-sex education does more good than harm, or whether it does any good at all. The battle pits the American Civil Liberties Union and women's groups against some who have been frequent allies…

In 2008, the Florida state legislature, by a nearly unanimous vote, rushed passage on a statute that allowed sex segregation in public school classrooms. According to the version of the bill that passed through the Florida House, sex-segregated public school classrooms would be an expansion of school choice and would be implemented only…