Using a rich dataset that merges student-level school records with birth records, and a student fixed effect design, we explore how the massive scale-up of a Florida private school choice program affected public school students' outcomes. Expansion of the program produced modestly larger benefits for students attending public schools that had a larger initial degree of private school options, measured prior to the introduction of the voucher program. These benefits include higher standardized test scores and lower absenteeism and suspension rates. Effects are particularly pronounced for lower-income students, but results are positive for more affluent students as well.