The role of ‘fair’ institutions in developing democratic legitimacy has received increased attention. Citizens who perceive – on basis of past experiences – that they are being treated fairly by authorities have been held to have greater trust in political institutions. However, previous studies on the relationship between procedural fairness and political trust have not paid sufficient attention to individuals with limited first-hand experiences of authorities. We examine the relationship on an authority that virtually all individuals meet early in life: the school. Using structural equation modeling on unique panel data covering 1500 Swedish adolescents (ages ranging from 13 to 17), we find a reciprocal relationship: personal encounters with school authorities shape young people’s political trust; however, the images that adolescents get of the political system (through family, peers, media and so on) have also consequences on their perceptions about the authorities they encounter in their daily lives. The analysis increases our understanding of how individuals form their political allegiances by showing that the relationship between fairness and trust is more dynamic than has previously been suggested: neither an accumulated set of experiences of authorities nor formal ties with political institutions (as voters and so on) are required for a relationship to emerge.