The present study investigates the joint effect of the quantity and quality of out-of-school activities (i.e., employment and leisure) on academic outcomes (i.e., well-being, study attitude, and academic performance) among 230 undergraduates. A series of hierarchical regression analyses show that spending too much time in both employment and leisure activities has negative relations with undergraduates' academic outcomes. Work-study interference fully mediated the effect of time engagement in student employment on students' reported well-being. These findings support a conflict perspective on multiple role engagement. However, results also show positive effects of activities depending on job demand and autonomy and level of autonomous motivation to engage in these activities. We conclude that out-of-school activities can be beneficial for students' academic outcomes and preparation for the labor market when perceived as relevant for their academic study and performed in a balanced, autonomous way. (Contains 3 figures and 5 tables.)