Lack of adjustment or school failure is of concern to educators, child welfare workers, educational, and school psychologists as well as parents, but there are few studies on this aspect of education, especially among late adolescents. Furthermore, there is a lack of research on teachers as socialization agents as an independent variable in adolescents’ school adjustment. The present study was conducted to explore how upper secondary school students’ perceptions of teacher socialization practices were related to motivation for continued education, school alienation, intention to quit school, truancy, and class absence. The sample consisted of Norwegian adolescents aged 15- to 18-years-old (n = 564) in vocational and general educational courses from one upper secondary school. Perceptions of teacher socialization practices accounted for unique variances in school adjustment. Of the teacher socialization variables, academic support best explained variances in school adjustment. The findings suggest that the associations between teachers as socializing agents and motivation for continued education were relatively strong, but the other associations were relatively modest. The limitations and implications of this study are discussed.