The theme of this paper is student interest in future natural sciences–related careers. It is based on data from the Programme for International Student Assessment (PISA) survey that in 2006 focused attention on the science literacy achievements of students. The paper uses the methods of linear regression modelling and structural equation modelling in analysing the impact of student family background on the formation of interest in future science-related educational and occupational careers relative to the impact of school characteristics. An almost negligible impact of family on interest formation was found in the Czech Republic, Germany, Finland and Norway. On the other hand, the impact of school from the point of view of preparing students for future educational and career trajectories was found to be strong in all countries studied due to their influence on the degree of student awareness of science-related career opportunities (‘science’, as used in this paper, refers to the natural sciences). From the educational policy point of view, the results support the importance of career guidance.