Description: ‚Chemie im Kontext' (CHiK, chemistry in context) is a large-scale innovation project which aims at the improvement of chemistry teaching in secondary schools in Germany (funded by the German Ministry of Education and the participating federal states). The theoretical framework of our approach consists of theories on situated learning (e. g. Anchored Instruction, Cognitive Apprenticeship): The focus of teaching and learning is on relevant and authentic problems which are embedded in authentic contexts (e. g. daily-life contexts like "food"). Based on these contexts, students are involved in self-directed and inquiry-oriented learning activities. At the end of a teaching unit, the underlying concepts are elaborated and integrated to other key concepts of chemistry. 'Chemie im Kontext' aims at enhancing motivation and interest of students for science - especially for chemistry. Furthermore, this approach should foster the acquisition of applicable knowledge and cross-curricular competencies. For the implementation of CHiK, a so-called "symbiotic approach" has been developed. This approach aims at overcoming the often bemoaned problem that innovations in teaching and learning are often not accepted or 'falsified' by practitioners. Our implementation approach can be characterised by two aspects: (1) It is a co-operative and symbiotic process, within which teachers and researchers continuously work together in learning communities, implementing and revising the framework of CHiK. The term "symbiotic" points out the reciprocal dependency and profit of researchers and practitioners. (2) The process is a developing approach: Changes and revisions of the framework of CHiK are regarded as important to adapt our project to different situations and conditions. In the empirical research we will present at the conference, we focus on the following questions: (1) Does CHiK foster motivation and interest for chemistry of students? (2) Is it possible to use the symbiotic approach for implementing an innovation in teaching and learning and is this approach successful? To answer these questions, a longitudinal study (3 years) has been conducted. Teachers (N = 158) and their students (N = 2154) completed questionnaires at the beginning of the project (baseline) and after every school year. Further, some in depth interviews with teachers and students give a more detailed insight in the effects of the project. The data analysis reveals that the approach of context-based learning is able to enhance students' motivation and interest for learning chemistry. Our analysis shows that the relevance of the chosen contexts is especially important for interest and motivation. Still there seems to be a certain danger that self-directed learning activities lead to students to a feeling of "getting lost" in the context. Thus, a phase of elaborating the conceptual knowledge and a structuring of the learning activities seem to be an indispensable instructional offer. Our data also showed that the learning communities have been supportive in helping teachers to change their teaching towards a more context-based and student-oriented teaching. Further, the continuous co-operation of researchers and practitioners seem to be a very suitable approach for implementing innovations in schools. The results are discussed with respect to recent findings of research on school-innovation. Different German innovation projects are compared, in order to conclude on the fostering and restricting conditions of school innovation.