This dissertation contains three chapters that study individuals' willingness to work, factors that influence their human capital development, and the interaction between their human capital investment decisions and labor supply.Chapter one examines how college students choose their credit hour enrollment, labor supply, and borrowing, paying particular attention to the role of wages, financial resources and beliefs. To formalize these relationships, I construct a dynamic structural model where students choose their credit hours, work hours, and borrowing to maximize lifetime utility. I collect data from two sources to estimate the model: (1) a unique survey of Michigan State undergraduates eliciting their employment history, family financial support, beliefs about the returns to studying and beliefs about earning a high GPA, and (2) administrative data from the University. Estimates of the model suggest that students' credit hour decision is inelastic with respect to changes in financial aid, tuition, beliefs, or wages. Students' labor supply and borrowing decisions are responsive to changes in wages, and for a subset of students, changes in beliefs. I also conduct two counterfactual simulations, increasing the minimum wage and making college tuition free, and evaluate how these policy changes affect student decisions and outcomes.The second chapter studies the relationship between the gender composition of a student's peers and two of their non-cognitive factors: sense of belonging and self-worth. Using data from Add Health and exploiting idiosyncratic variation in the share of female peers across grades within schools, I find positive but small effects of a higher share of female peers for male students. I do not find statistically significant effects for female students, but I can rule out large positive effects.The third chapter, jointly written with Todd Elder and Steven J. Haider, estimates how the wage elasticity of labor supply has changed for single and married men and women over the last two decades. The wage elasticity of labor supply is arguably one of the most fundamental parameters in economics, but despite the central role of this parameter, few studies have examined how it has evolved past the early 2000s. We find robust evidence that the labor supply elasticities for all four demographic groups have increased modestly. For women, this finding is a substantial departure from earlier evidence. We also contribute to the literature on the robustness of discrete choice labor supply models by estimating elasticities under a variety of assumptions and specifications. Our estimated trends are remarkably similar across specifications.