From a pedagogical view, constructivist perspectives on learning and instruction emphasise independent learning, meta-cognition, “active learning” or learning from experts (cognitive apprenticeship). This goes hand in hand with six central elements of multi-age teaching, like 1. Multi-age grouping, where elder pupils may become tutors of the younger ones, 2. The role of the teacher as a facilitator (Hoffman, 2002), 3. Common learning content but different levels, 4. Formative assessment (Hargreaves, 2001), 5. Cooperative, and 6. Individual learning. Based on an input-output-model, with the six elements of multi-age teaching as process indicators, we measure teacher beliefs, school and team resources as interacting variables with multi-age teaching. The resulting research questions for our survey are as follows: (1) Is it possible to proof the construct multi-age teaching empirically with the help of a structural model? (2) How are context variables like teacher-beliefs, school and team resources related to our construct of multi-age teaching? Our sample consists of all primary schools with multi-grade classes in the three participating regions of Switzerland and Austria. All teachers fill out an online-questionnaire. The survey items will be summarised in scales. To test the relationships of the scales, structural equation models will be constructed.