This article features Ruth Wright Hayre, Philadelphia's first black high school teacher and principal whose work at William Penn High School for Girls became a model for counseling and motivation programs at other majority-black high schools in Philadelphia, expanding educational and career opportunities for thousands of "able" students. Through the efforts of Hayre, her fellow teachers, community members and students, and like-minded educational activists like Floyd Logan, William Penn High School for Girls became one of the rare success stories among Philadelphia public schools in this era. Hayre demonstrated that college preparatory education was possible in low-income minority schools and she ensured that "able" students were not left behind in the city's comprehensive high schools. The author discusses Hayre's efforts to expand educational opportunities for black high school students in Philadelphia and the struggle for equality in Philadelphia's black high schools from 1955 to 1965. He also discusses how Hayre creatively implemented Conant-era ideas about standardized testing and curriculum tracking to the benefit, not the determent, of black students. (Contains 5 figures and 86 footnotes.)