Both policymakers and scholars disagree about the effects and suitability of citizenship education standalone courses. Extant evidence about their effects is mixed and inconclusive. This article exploits the discontinuities generated by changes in Spanish education policies to identify the long-term effects of civic education on multiple outputs usually set as the policy goals of these courses: political engagement, institutional support and political values. In 2007, a new standalone citizenship education subject was introduced in the Spanish school curricula. This subject was then progressively removed from the curricula until its disappearance in 2017. These changes gave rise to exogenous variation in exposure to civic education between young individuals born in different years. In this article these policy changes are exploited to identify the effects of citizenship education through a regression discontinuity design that draws on a 12-wave panel survey. The results point to the emergence of a generation of critical - yet passive - citizens as a result of the implementation of a standalone citizenship education subject in Spanish schools. Supplemental data for this article can be accessed online at: https://doi.org/10.1080/01402382.2021.1917153 .