Arrows first? – a qualitative exploration of how mechanistic organic chemistry is taught in the A-level curriculum in England†

Student difficulties with the curly-arrow model in mechanistic organic chemistry have been the subject of a great deal of research. The inclusion of curly arrow mechanisms in an organic chemistry curriculum presents an opportunity for students to develop skills in problem solving which are useful both in higher education and employment so the topic has utility beyond content knowledge. An arrows first approach to organic mechanism has been suggested as an effective teaching strategy to prevent the development of misconceptions which may undermine a student's achievement and cause difficulties with further study. Through the lens of the A-level in chemistry, a regulated national qualification covering significant mechanistic chemistry content, we have evaluated a range of evidence to explore how mechanistic organic chemistry is taught. Taking a holistic overview of the curriculum we show that many aspects of the curriculum support an arrows first approach to teaching including the implemented and assessed curriculum, both influenced by examination boards. However we also found that a much larger proportion of teaching time, effort and assessment is devoted to case-study mechanisms, generally organised by functional group. These may be memorised by students, undermining an arrows first focus. Moreover, although we found our sample of teacher respondents were generally positive about teaching the fundamentals of the curly arrow model we also found a lack of accessible classroom resources and professional development to support teaching using an arrows first approach. In light of the published aims of the A-level in chemistry, this research has implications for policy and practice in the 16–18 chemistry curriculum for educators, examination boards and regulators.