While the 2006 Progress in International Reading Literacy Study (PIRLS) assesses the average ability of German primary school students as being higher than average, the Programme for International Student Assessment (PISA) studies (OECD, 2000, 2003, 2006) ranks German secondary school
students at a considerably lower level. This article examines whether a teacher's recommendation for the secondary school track and class repeating are causes for these ability differences. According to the estimates, failures as a result of teachers' recommendations given at the end of primary
school are an important reason for the differences between the two types of studies. Being required to repeat a school class amplifies the inefficient management of children's abilities.