This paper examines whether social stigma or peer sanctions associated with academic achievement or effort adversely affects girls’ school performance (in absolute terms, or relative to boys). The effects of the introduction of a point system and “leaderboard” into computer-based math and English courses in high schools in California revealed previously hidden information, namely who the top performers were in the class. This study finds that the system led to a very large decline in performance for students who were at the top of the class prior to introduction (those most “at risk” of being in the leaderboard), and a smaller increase in performance for students at the bottom of the class. Despite results from previous studies on stigma and performance, this study finds no differences in these effects between boys and girls in either English or math. The net effect of the point system and leaderboard worsen overall performance. Speaker: Robert Jensen, Professor of Business Economics and Public Policy, University of Pennsylvania