The study examined the individual characteristics and consequences of psychological group processes that may lead some students to gain a reputation for being politically knowledgeable and verbal in class (a political reputation). Two normal samples of Swedish students were used, 13-year-olds (N = 835) and 16-year-olds (N = 795). Longitudinal data over one year were analyzed and showed that youths’ political reputation in class is established very early. Cross-sectional predictions showed that political interest predicted political reputation in class positively, and social fear predicted political reputation negatively in both cohorts. In addition, having a political reputation predicted increased political interest and political efficacy over one year. Further, mediation analyses showed that youths’ political predispositions, their political interest and political efficacy at T1, significantly operated on interest and efficacy at T2 via the political reputation. This suggests that political reputation partly functions as a booster of youths’ initial political predispositions over time. Future research is needed into the long-term consequences of having a political reputation.