Luhmann's theory allows for a reflection on teaching as interaction system. According to Luhmann, the interaction system of teaching accomplishes the function of the education system, i.e. transforming psychic systems in persons. The education system fixes the social structures of teaching, i.e. conveyance and evaluation of knowledge. However, the unpredictable effects of pupils' reactions to teaching has led to observe the necessity of a unity of conveyance and evaluation of knowledge on the one hand, and sensitivity for pupils' participation on the other. Sociological studies and pedagogical reflections have focused on the inclusion of sensitivity in teaching and on the relation between technical and sensitive systems of interaction in local communities and international settings. Sociological research shows that this relation implies a differentiation of structures of interactions. The relevant question is if and how far this differentiation can be pursued in the education system, and with what consequences.