Do young people in US states that have a high stakes exam in civics have a higher level of civic knowledge? We hypothesize that state-mandated assessments result in greater political knowledge both for students in high school and young adults in the years immediately following. We expect that assessments have the biggest effect: a) in states where they are a requirement for high school graduation—the incentive hypothesis; and b) on young people with less exposure to information about the US political system at home, specifically children of immigrants—the compensation hypothesis. We focus first on high school students, using the 2006 and 2010 Civics Exam of the National Assessment of Educational Progress. Then we draw on a large national survey of 18-24 year-olds. We find evidence for the incentive and compensation hypotheses in both datasets.