Based on empirical evidence on effective learning for active citizenship gathered in North America my papers argues that citizenship education should be made a cross-curricular reponsibility of an entire school embedded in the structure and culture of schools rather than a curricular standard of particular subjects such as history or social studies. The paper will then present a comprehensive model for cross-curricular citizenship education based on two didactical pillars: "Democratic Communication" on the one hand and "Learning for Public Responsibility (Service Learning)" on the other hand. Based on qualitative case studies in German primary and secondary schools (conducted in the German school development programme: www.blk-demokratie.de) I will then discuss implications this new way of educating for citizenship in schools has for both the structures and the culture/ethos of schools.