The success of teaching is depending on a couple of factors: on how far students are involved into lectures, on the material, its completeness and on co-learning of students. Involvement of students into lectures means, being able to follow the thoughts of the teacher, ask questions and make comments. The material must be presented in a suitable form and essential parts of it have to be available during the whole learning process, for preparing participation in lectures and exercises as well as for exams. For more effective learning and training of social abilities, working in groups of co-learners has to be encouraged. Mobile and ubiquitous computing offer new possibilities to achieve these goals by increasing the awareness in class and supporting an active participation of students. By promoting existing concepts and enabling new ways of application sharing, the project SASCIA (System architecture supporting cooperative and interactive applications) aims at developing a framework for multiple applications to support teaching in collocated, remote and hybrid scenarios. Its core is composed of components to capture and distribute context information about sessions, participants and those applications that are used during a lecture or encounter among students. A configurable floor control was designed to cope with a wide spectrum of applications and learning situations. For some cases, even a control for semantic consistency can be necessary. In combination with a suitable user and session management, a whiteboard for annotations and a recording facility to support latecomers as well as subsequent replay, these components are providing the required functionality. As a consequence, SASCIA offers remote control and viewing facilities to all participants during lectures and co-learning sessions. That means, usage of a lot of facilities like applications, pointing and annotating in application windows are available to everyone by leaving teachers the right to interrupt at any time. All public annotations as well as private ones can be stored and replayed afterwards. By offering state information about everybody in class with proper regard of privacy concerns, participants are enabled to address each other more personally. This holds especially for teachers getting direct feedback on their presentation. For discussions without a teacher being present, SASCIA provides collaborative ways of experiencing teachware and a voting mechanism to support ad hoc encounters and peer relations among participants. As demonstrated by measurement values with a first prototype, the performance of the whole system is acceptable. Further evaluation and experiments in real class situations are planned for the next semesters.