Argys, L.M., Rees, D.I., Averett S.L., & Witoonchart, B. (2006). Birth order and risky adolescent behavior. "Economic Inquiry", 44(2), 215-233 demonstrated that a strong link exists between birth order and adolescent risky behavior. Using data on 10th graders from the National Education Longitudinal Study of 1988, we extend the work of Argys et al. by examining the relationship between birth order and participation in school sports and other extracurricular activities. Our results suggest that having an older sibling is associated with an increased probability that males played baseball and football, were members of the school swim team, and participated in cheerleading. Female 10th graders with older siblings were less likely to engage in a variety of extracurricular activities including school band, community service, and yearbook. These results provide additional evidence that birth order is related to adolescent behavior.