The purpose of this study was to compare the relationships that exist between computer use and science achievement for 15-year-old students in the USA and Germany, based on data from the Program for International Student Assessment (PISA). The results of this study show that what has an effect on science achievement is the way in which computers are used. The results indicated that students who used computers frequently at home, including for writing papers, tended to have higher science achievement. Students who had frequent availability of computers at school, who used them at that location, and who frequently used computers for programming had lower levels of science achievement.