Generally, several main reasons for countries and governments to support creating positive relationship to (natural) science in young people can be mentioned. The endeavour to strengthen the science expert base should be one of the key aspects of educational policy (OECD, 2007; Palecková, 2007). This paper analyzes data from PISA 2006 using linear regression and structural equation modelling to determine factors influencing science literacy and interest in science. The analysis studies the impact of student family background on science literacy and on the formation of interest in future science-related educational and occupational careers compared to the impact of school. We focus primarily on students attaining best science literacy test scores – the so-called high-achievers (OECD, 2009a, b). Our results reveal that the impact of family on interest formation is almost negligible in the Czech Republic, Germany, Finland and Norway (countries represent different proportion of high-achievers). 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. Our analyses have also shown that the degree of student awareness of the science-related career opportunities has the strongest share in the variance of the dependent variable “interest”.