Trust in institutions and political participation are both essential for democracy. This paper proposes modeling trust in institutions among 14-year-old students in schools comparatively using ICCS 2016 data from 13 European countries. Data include more than 54,000 students in their eighth grade of schooling. Based on previous studies, we hypothesize to find that social media harm trust in institutions and therefore negatively affect civic and democratic participation. Trust and civic culture systems are studied using SEM. Results indicate that trust in social media indeed negatively influences trust in institutions in almost all European countries, which in turn reduces expected political and electoral participation of students.