Previous research has found that male high school athletes experience better outcomes than non-athletes, including higher educational attainment, more employment, and higher wages. Students self-select into athletics, however, so these may be selection effects rather than causal effects. To address this issue, I examine Title IX which provides a unique quasiexperiment in female athletic participation. Between 1972 and 1978, U.S. high schools rapidly increased their female athletic participation rates (to approximately the same level as their male athletic participation rates) in order to comply with Title IX. This paper uses variation in the level of boys' athletic participation across states before Title IX as an instrument for the change in girls' athletic participation over the 1970s. Analyzing differences in outcomes for both the pre- and post-Title IX cohorts across states, I find that a 10 percentage point rise in state-level female sports participation generates a 1 percentage point increase in female college attendance and a 1 to 2 percentage point rise in female labor force participation. Furthermore, greater opportunities to play sports leads to greater female participation in previously male-dominated occupations, particularly for high-skill occupations.