Environmental Education (EE) is pivotal in fostering awareness, attitudes, and skills necessary for sustainable development. With pressing environmental issues like climate change, deforestation, and pollution, evaluating EE programs has become essential to ensure their effectiveness and relevance. This paper explores various research methodologies—quantitative, qualitative, and mixed methods—used to assess the impact of environmental education initiatives. It discusses their strengths, limitations, and applicability in measuring cognitive, behavioral, and attitudinal outcomes. A suggested methodological framework and a case illustration highlight practical approaches to evaluation. Understanding and applying these methodologies not only improves existing programs but also informs policy decisions, scaling, and future program development.