This evaluation of a pilot GCSE course designed to enhance scientific literacy focuses on teaching How science works: how it relates to the 'science explanations' component and teachers' and students' reactions. A combination of research techniques (including observations, interviews and surveys) was used. The overall response was positive, but the findings suggest the need for: more resources to promote inter-student collaboration, greater use of interactive techniques to elicit student contributions, and more explicit teaching of how to interpret texts.