Stability and consistency in secondary schools' effects on students' GCSE outcomes over three years

This paper reports the results of a UK study investigating the issue of differential school effectiveness. The size of overall school effects versus departmental differences in effects on 16 year old students' General Certificate in Secondary Education performance are examined, as well as the internal (within school) consistency of departmental effects across six GCSE subject outcomes and the stability of school and departmental effects across three GCSE cohorts (1990-1992). A value added approach is adopted, controlling for selected student intake measures (such as attainment at secondary transfer). The findings of multilevel analyses suggest that very few schools perform both consistently (across subjects) and with stability (over time). The implications of the results are discussed in relation to the publication and interpretation of schools' examination results as well as the use of school and departmental effectiveness measures for school self-evaluation.