In the days after, department heads would typically work out how well their department had done against national pass rates, or
against pupil prior achievement, and write reports only for internal use.
Although 96.7 per cent of grammar school
pupils achieve five A * to C GCSEs
against a national average of 57 per cent, the EPI says this is not evidence of better grammar school performance, but is in fact likely to be driven by the high
prior attainment and demographic of
pupils at selective schools.