Whether enough highly qualified STEM workers are being educated and trained in the UK is an important question. The answer has implications not only for educators, employers and policymakers but also for individuals who are currently engaged in, or are considering entering, education or training in this area. Set against a policy backdrop that prioritises students studying more science for longer, this paper considers long-term patterns of participation in STEM education -- from school science through to graduate entry into the highly skilled STEM labour market. Using a unique dataset that extends across seven decades and comprises many hundreds of thousands of students, the paper finds that patterns of participation in most STEM subjects have varied little over the period considered; suggesting that efforts to increase the numbers of students studying science in school has had limited impact on the throughput of students who study STEM, including the pure sciences, at university level and, subsequently, on the number of graduates who would be available to undertake highly skilled work in areas for which degree-level skills are a pre-requisite.