This chapter develops the argument of Bhimani (2022, 2024) that, despite the perception of eugenics as a discredited historical discourse, eugenic thinking in educational policy in England has never really gone away. While the language of eugenics and its use in education policy may have changed over the last century, we challenge the idea that its effects are no longer evident in classrooms today, and assert that it remains essential to identify and recognise eugenic discourses presented as progressive policy if we are to challenge the exclusionary pressures experienced by teachers and students in classrooms today. Firstly, we explore the impact of the eugenics movement in England in the first part of the twentieth century on how concepts such as intelligence, Special Educational Needs and school improvement are understood. Drawing on a range of historical documents, the development of eugenic thinking in relation to the measuring, ranking, and labelling of children in English school contexts is described. Secondly, we demonstrate the resilience of eugenic discourses of 1920s England in education policy in the twenty first century by exploring contemporary English educational policy on school exclusion. This analysis illustrates the enduring tendency of the education system to rank and sort pupils more ‘deserving’ of a mainstream education, whilst creating seemingly more humane ways to exclude children and young people. We advocate for continuing professional development for pre-service, newly qualified, and experienced teachers that incorporates teaching on the legacies of eugenics in education policy and its direct impacts on children and young people who are excluded.