This set of five papers, written in German with abstracts in English, was collected by the Institut fuer Didaktit der Mathematik (Institute for the Teaching of Mathematics) at the University of Bielefeld in West Germany. In the first paper, Bauersfeld considers domains of subjective experiences as the best issue for an interactive theory of mathematics learning and teaching, using transcripts and interpretations of classroom discourse. Krummheuer, in the second paper, deals with communication problems between teacher and pupils, using instances from beginning algebra. Lorenz discusses learning problems in primary mathematics education in the third paper, describing work with underachieving students. In the fourth paper, Voigt uses transcripts of several lessons introducing probability calculus to make a microethnographic study of typical problem-solving processes with mathematical tasks. Bussman, in the final paper, attempts to show that current paradigms in mathematics education literature thematize both teaching-learning processes and educational processes, but neglect mathematical abilities. (MNS)