In a time of cultural pluralism and legitimation crisis (Habermas), there is an increasing uncertainty among teachers in Sweden about with what right they are fostering other people's children. What does it mean to teach "common values" to the coming generation? How do teachers find legitimacy and authority for this endeavour, not as family members or as politicians, but as teachers? To respond to this uncertainty, the paper takes the public/private distinction as a starting-point for rethinking the place of the school. Drawing on the work of Hannah Arendt and of Jan Masschelein and Maarten Simons, it argues that the school is an in-between place--a place that transforms values into "common goods" and turns fostering into a teaching matter. The overall purpose of the paper is to sketch out the consequences of this "in-betweenness" for what it means to find one's voice as a teacher in fostering the coming generation.