Are Summer‐born Children Disadvantaged? The Birthdate Effect in Education

Abstract Summer‐bom children did not perform as well as autumn‐born children on the APU Science Survey tests. There is bound to be some confounding of birthdate with length of schooling, but comparisons with foreign studies support the view that it is the age position of the pupil within the class that is the main explanatory factor for this performance difference. A hierarchical linear model (using HLM software) enabled evidence of a birthdate effect to be identified in the performance of pupils aged 11, 13 and 15. The effect is strong at the younger age but is still visible in the older age group. This paper urges teachers to acknowledge these artificial differences in performance when assigning pupils to different ability groupings related to National Assessment levels.