When people interact with others, they form expectations about what these others will say or do. These expectations can also have consequences as they can lead people to behave in ways that conform with the expectations. Such social interactions also occur within the domain of education. Teachers develop expectations for students academic performance which could in turn have important consequences. Especially for students who are at risk for school failure such as ethnic minority students or students from lower socioeconomic backgrounds, the impact may be large. Within the educational research field, numerous studies have investigated predictors and effects of teachers expectations. Nevertheless, shortcomings in the existing knowledge base remain. In order to address some of these gaps, four studies are carried out that aimed at identifying important antecedents, consequences and moderators of teachers expectations with respect to ethnic minority students and students from lower socioeconomic backgrounds in Flanders. All four studies are based on data from the large-scale longitudinal SiBO-project (Dutch acronym for Trajectories through Primary Education), comprising a representative cohort of approximately 4000 students followed from kindergarten until the end of sixth grade and beyond. Information is gathered on students cognitive skills and on characteristics of their family, classroom and teacher. The effects of teachers expectations are investigated both cross-sectional (i.e., in kindergarten) and longitudinally, across several grades in elementary school. Data are analysed by means of structural equation modeling and multilevel regression analyses.By means of an integrated moderated mediation structural equation model, the first study reveals that teachers expectations in kindergarten mediates the association between students SES and their later language and math achievement, controlling for students ethnicity, prior achievement and gender. Furthermore, students ethnicity moderates this mediation effect of teachers expectations with respect to math outcomes. The second study shows that teachers have higher expectations for girls and students with a higher SES than for boys and students with a lower SES, controlling for students prior achievement. The multilevel regression analyses also demonstrate that the expectations are higher in classes with more low-SES students than in classes with more high-SES students. Furthermore, teachers expect more from minority students when these students belong to classes with a larger proportion of minority students than when these students belong to classes with a larger proportion of majority students. By using a latent sum and difference structural equation model, the third study shows that teachers and parents expectations in kindergarten are, both independently and congruently, associated with students achievement, controlling for their prior achievement. These associations are most pronounced for children from lower socioeconomic backgrounds. Furthermore, if teachers and parents have differential expectations, the effect of the parents predominates. In the fourth study, the results of the longitudinal reciprocal structural equation model point towards direct effects of teachers expectations on students achievement within one school year and to indirect effects across several school years through a transfer of expectations of different teachers over time. The associations between expectations and achievement during elementary school do not differ for majority and minority students nor for different SES groups.To conclude, teachers have differential expectations concerning their students in kindergarten and in elementary school. Furthermore, teachers expectations in turn affect students achievement outcomes. Although in general the effects are rather small, they become larger for students from lower socioeconomic backgrounds, when teachers expectations match the expectations of parents and by means of a transfer of expectations of different teachers over time. status: published