This yearbook includes four articles, one of which is written in German. The first article, "The Development of Mathematics Attitudes on the Upper Level of the Comprehensive School" (Olavi Karjalainen), examines the development of children's attitudes towards mathematics and the factors related to the development during the upper level of the comprehensive school. In this study the same pupils were followed through the entire comprehensive school (grades 1-9). The second article, "The Significance of Cognitive Psychology to Mathematics Teaching and Didactic Research" (Tapio Keranto), outlines the contribution of psychological research of cognitive processes and strategies to didactic research in mathematics and thereby to the development of mathematics teaching. The last two articles deal with problem solving and applications. "Problem Solving and Applications in the Finnish School Mathematics Since 1970" (Pekka Kupari), examines the role and development of problem solving and applications in comprehensive school mathematics during the past 18 years. The paper in German, "Offene Probleme in Mathematikunterricht" (Erkki Pehkonen and Bernd Zimmermann) describes the Finnish-German cooperation project, through which new forms of teaching problem solving in mathematics are searched. (YP)