Education for Sustainable Development (ESD) is widely presented as an important educational response to current sustainability challenges, yet its conceptual foundations remain contested, particularly in the context of digitalization. This chapter examines how learning, agency, and normativity are conceptualised within sustainable development education when digitalization is approached as a condition for learning rather than as a neutral technical instrument. Drawing on conceptual perspectives from agricultural extension and development communication, the chapter reframes ESD as a communicative and participatory educational project oriented toward meaning making, interpretation, and dialogue, rather than the transmission of predefined competencies or behaviour. It interrogates the widespread portrayal of learners as “change agents”, examining how this expectation is embedded in normative assumptions about responsibility and desired social outcomes, and how agency can be understood as relational and mediated rather than individualised. The chapter also explores tensions between normativity, responsibility, and educational autonomy, and considers how these tensions are reconfigured under digital conditions. By integrating insights from extension, development communication, and critical studies of digitalization, the chapter clarifies the educational character of sustainable development education and offers a conceptual foundation for future work on learning and sustainability in digitally mediated contexts.