To enhance the student experience and improve student outcomes -- continuation, attainment, and employment -- higher education providers often implement curriculum changes and evaluate their effectiveness. But as interventions often only work directly with staff, rather than students, impact evaluation is challenging. This paper explores the introduction of extensive curriculum change to embed active learning and teaching. Qualitative interviews are used to explore the views of stakeholders, which inform the development of an evaluation framework, informed by Programme Theory evaluation (PTE), and examining short-term benefits, medium-term outcomes, and longer-term impact. The University will use the evaluation framework to monitor longer-term outcomes of the intervention. Together with PTE, evaluation frameworks apply to other higher education providers evaluating the impact of curriculum enhancement on student outcomes.