Test-based accountability pressures have had mixed effects on the student outcomes that they are intended to improve. Accountability policies have also resulted in transfers of less effective teachers into untested early grades and more effective teachers in early grades into tested grades, which could yield unintended negative consequences. In this study, we use a sharp regression discontinuity design to examine the effects of accountability-driven school reform on student outcomes and teacher mobility in 38 elementary schools assigned to reform in North Carolina. We find evidence of a small increase in chronic absenteeism and grade retention in grades K-2 in the first year of reforms. We also find suggestive evidence of negative effects on early literacy and reading comprehension, measured using formative reading assessments, in the first year that rebounded somewhat in the second year. Schools labeled low performing reassigned low-effectiveness teachers from tested grades into untested early grades, though these assignment practices were no more prevalent in reform than control schools. Our results suggest that accountability-driven school reform can yield negative consequences for younger students that may undermine the success and sustainability of school turnaround efforts.