There is a little information about whether and if so how student aspirations for college change over time. We introduce a conceptual model to explain how student aspirations may change over time, utilize panel methods to examine the extent to which this happens during high school, and investigate which factors are associated with such changes. We find that students increase and decrease their college aspirations over time, and such changes are strongly related to high school performance and family mobility. The results suggest that postsecondary stakeholders may need to focus more on the complexities underlying changes in student aspirations.