We begin with a simple summary analysis of the medium-term relationship between mobility and academic performance, comparing movers with their stable peers. These models are most similar to what has been estimated in the previous literature and therefore serve as a good starting point for the discussion. As shown in the first two columns of table 2, students who make summer moves earn lower scores in both ELA (0.041) and math (0.072) in the years following a move, as do mid-year movers (0.031 and 0.045 in ELA and math, respectively), controlling for student characteristics and prior performance only.²⁰ Introducing student fixed effects and moving to the difference-in-difference results (columns 3 and 4) substantially increases the magnitude of the coefficients: Summer movers perform 0.079 lower in ELA and 0.118 lower in math, and mid-year movers perform 0.039 lower in ELA and 0.131 lower in math than their stable peers. The finding that the negative relationship between mobility and performance is larger with the inclusion of student fixed effects suggests that movers as a whole are slightly better performing that non-movers (which is consistent with the descriptive results in table 1).