School achievement of non-Western ethnic minority students in the Netherlands often lags behind the achievement of their native Dutch peers. Non-Western ethnic minority students also often seem to show relatively more problematic behavior. In this dissertation, two possible explanations for these differences in school adjustment (i.e., academic performance and problem behavior) were examined. Both of these explanations were focused on affect regulation processes in the classroom. The studies took place among first year prevocational students and sixth grade students. In the first part of this dissertation (Chapters 2 and 3), the focus was on examining associations between negative stereotypes (i.e., stereotype threat) and the school performance and behavior of ethnic minority students in the Netherlands. An intervention aimed at making students more resilient against stereotype threat was tested (Chapter 3). In the second part of this dissertation, it was examined how the affective quality of the teacher-child relationship was associated with the behavioral adjustment of ethnic minority students in the Netherlands (Chapter 4).