Universities are an important part of the process of change taking place in society. However, this is often overshadowed by these institutions giving priority to technocratic models in the relationship between science and society. In this context, according to Habermas, theories can serve to clarify practical questions and guide praxis into the right actions (social emancipation and rational autonomy). Habermas introduces the need to evaluate the particular contexts in which scientific arguments are made and assessed. The aim of this study was to develop a set of assessment criteria for education for sustainable development in higher education curricula. These were developed in line with Habermas by introducing further adaptions within the context of education for sustainable development. These criteria were tested in a blended learning master's programme in Environmental Citizenship and Participation at the Universidade Aberta, Portugal. The following research tools were used as follows: (i) a questionnaire survey to the graduates; (ii) content analysis applied to the information guide and to the abstracts of the dissertations that were produced. The case study revealed that an absence of theoretical frameworks could lead to inconsistencies between theory and praxis. Improvements to curricula are then drawn from this study.