Teacher certification and student achievement in Swedish compulsory schools

This study examines how the teaching staff composition with respect to certification affects student achievement in compulsory Swedish schools. The share of non-certified teachers in compulsory schooling has increased dramatically during the last decade, starting a large debate about school quality. We apply an instrumental variable approach to estimate the causal effect of the percentage of non-certified teachers on student achievement. We find, in our preferred specification, that a one percentage point increase in the share of non-certified teachers is expected to decrease the average student’s GPA ranking with about 0.6 units. A substantial effect if one considers the large differences in certification rate that do exist between schools and municipalities. The effect also appears to be stronger for students with highly educated parents.