Analysis of National Value-added Datasets to Assess the Impact of Selection on Pupil Performance

The impact of selective education systems on pupil performance has long been a contentious issue, but the advent of national value-added datasets linking performance across key stages for the majority of pupils in England has enabled detailed analysis to throw some light on the issues. The main finding has been a distinct difference in Key Stage 3 test levels for pupils on the 'borderline' between grammar school and secondary modern school, even when prior attainment is taken into account. Possible explanations for this apparent 'grammar school effect' are discussed.