This study was funded through the Education Endowment Foundation’s 2019 ‘School Choices’ round. It aimed to investigate the extent of, and rationale for, offering a two- or three-year KS4 in England and explore how the choices made by schools about their length of Key Stage 4 (KS4) affected pupil outcomes at GCSE.
This study used a Quasi Experimental Design (QED) which aimed to compare the differences in pupil outcomes between two groups of schools – those offering a three-year KS4 compared to those offering a two-year KS4.
However, it was not possible to achieve a strong match through the QED, with the two groups of schools on different GCSE performance trajectories prior to the KS4 length policy change. For this reason, while this study reports some observed differences in the outcomes of interest, the research team is unable to make any claims as to whether these differences are due to the length of KS4. This caveat applies to the primary outcome (maths attainment), the secondary outcomes (English literature and 5 A*-C grades at GCSE), and to a subgroup analysis on the maths performance of everFSM pupils.
The evaluator’s recommendation is that schools should not make a decision about the length of their KS4 on the basis of the impact evaluation (QED) findings reported here.