The Case Study Project is a component of the Third International Mathematics and Science Study (TIMSS), and this volume-To Sum It Up-is one of five publications in the Case Study Project. The Project was designed to provide in-depth information on education in three nations: Germany, Japan, and the United States. The four research topics which were the focus of the case studies in each of these countries were selected by the U.S. Department of Education in an effort to collect qualitative data which would complement and amplify the quantitative information obtained through the main Third International Mathematics and Science Study. The topics investigated in the Case study Project were: education standards, dealing with differences in ability, the place of school in adolescents` lives, and the training and working conditions of teachers.