Both the German and the Austrian school systems are structured and organized along the idea of sorting learners towards ‘the correct type school’. Along this structural implication didactical concepts have been developed that are orientated in one or the other way the idea of sorting. Therefore the current demand or educational policy of acknowledging diversity in class – while keeping up a sorting structure of the school system – challenges teaching processes. Teachers are seen as one key factor for developing acknowledging forms of education and/or recognition on different types of students. There is a lack of knowledge on the concepts of differences that are constructed or referred to in teaching processes. My research tries to fill that gap by asking for concepts of differences teachers are referring to in their teaching. The main point of my research is to unveil these constructs, especially those ones that teachers are referring to when choosing teaching methods and other aspects of teaching. Data from focus group interviews will be presented.