This study investigated to what extent primary school teachers' perceptions of their students' ability and effort predict developmental changes in children's self-concepts of ability in math and reading after controlling for students' academic performance and general intelligence. Three cohorts (N?=?849) of elementary school children and their teachers were followed for four years. Children's self-concepts and performance ability in math and reading were measured annually during Waves 2-4. Teachers rated the children's ability and effort at each of the four waves. Domain-specific differences and developmental changes could be identified in the associations between teachers' perceptions and children's ability self-concepts. Teachers' ability perceptions predicted children's concurrent and subsequent ability self-concepts in math and reading, whereas teachers' effort perceptions predicted children's math ability self-concept only at Wave 4. Analyses with multi-sample procedure showed that these models were similar for boys and girls and for children in different cohort groups.