Parochial and private schools in the United States have maintained opportunities for students to attend same-gender settings without interference from policies governing public education. The gender composition and curriculum of public schools, however, have been influenced by societal regulations and expectations that have often utilized same-gender schools or classrooms as a means to place females in a "separate and unequal" position relative to males. Experimentation with single-gender public schools was restricted in 1972 with Title IX legislation, which prohibited discrimination on the basis of gender or race in any educational program receiving federal funds. The No Child Left Behind (NCLB) Act of 2001 (NCLB) prompted a reinterpretation of Title IX through a provision for grant funds to encourage more focused research on single-gender programs in public schools. This paper examines: (1) historical gender-specific practices in Philadelphia, including Central High School's transformation from an all-male institution to a coeducational setting, and (2) implications of the "return" to same-gender public education resulting from NCLB and the reinterpretation of Title IX. (Contains 2 notes.)