In Germany the transition from primary to secondary school represents the decision for one out of three academical tracks leading to three different levels of graduation. Because it is difficult to transit from one track to another, this decision determines to a large extend student's future and reproduces social disparity (cf. Boudon 1974). Current social science tends to regard school track decisions as a rational choice in the student's family (cf. Breen & Goldthorpe 1997, Esser 1999). For this decision families take into account their individual experiences and orientate themselves at social structures - like the structure of the school systems or the function of graduation in life (cf. Erikson & Jonsson 1996, Becker 2001). What factors - beside the student achievement - determine the teacher's recommendation and the parents' decision respectively? Data from PIRLS (Progress in International Reading Literacy Study) and a German follow- up study (KESS 4) indicate that underprivileged students must show a higher performance than privileged students to get the same teacher's or parents recommendation. Other relevant factors for the transition from primary to secondary school are migration background and gender. These current empirical results are presented in the paper.