Although the "Janus v. AFCSME" (2018) decision fundamentally changed the institutional context for U.S. teachers' unions by placing all public school teachers in a "Right to Work" (RTW) framework, little research exists to conceptualize the effects of such policies that hinder unionization. To fill this gap, I exploit the different timing across states in the passage of RTW policies in a differences-in-differences framework to identify how exposure to a RTW policy affects students, teachers, and education policymaking. I find that RTW policies lead to declines in teachers' union power, but contrary to what many union critics have argued, I find that efforts to weaken unions did not result in political opportunities for education reforms nor did they improve student achievement outcomes.