The first essay in my dissertation investigates the impact of a state policy designed to reduce substance abuse. Prescription drug monitoring programs (PDMPs) are state-run electronic databases that track the prescribing and dispensing of controlled substances. I examine the impact of PDMP implementation on various measures of opioid pain reliever abuse. I estimate difference-in-differences models, and address possible policy endogeneity by controlling for pre-implementation trends and related state laws. The preferred estimates suggest that PDMPs reduced opioid abuse treatment admissions by 13.1%. However I cannot reject the null hypothesis that PDMPs had no effect on self-reported nonmedical use and overdose deaths. The second essay investigates the relationship between parental job loss and child health outcomes. I use data on parental job displacement and child health outcomes from the Panel Study of Income Dynamics (PSID). Parental displacement results in a drop in family income and employer-provided health insurance, which is only partially offset by an increase in public and privately-purchased insurance. I find that parental job displacement is associated with a significantly lower likelihood of mental illness diagnosis, and a higher likelihood of ever drinking and using marijuana. I do not find significant effects of displacement on depressive symptoms, health status, and smoking. The third essay is joint work with John Cawley and Joseph Price. This paper investigates one possible determinant of physical activity: the success of local sports teams. We hypothesize that individuals living in an area with a successful local sports team will be more likely to engage in that sport as a result of role model or bandwagon effects. We merge individual U.S. data from the Simmons National Consumer Survey with data on sports team performance for a variety of sports at the professional and college level. We estimate ordered probit models of participation in a particular sport as a function of local sports team success, with controls for demographics as well as fixed effects of time and geographic area. We find some evidence that children are more likely to participate in sport when local teams perform well, and find weaker evidence of such a relationship for teens.