This study aimed to analyse and understand the perception about Education for Sustainability from the perspective of secondary school students in the Basque Autonomous Community by means of a qualitative methodological strategy. Specifically, the study was conducted in four educational centres with a total of 39 students, through discussion groups in a total of eight meetings. Environmental education documents of the centres were analysed, and a non-participatory observation process was also applied. The main results showed that the students had sufficient knowledge and information about the socio-environmental problem; however, their behaviour did not correspond to their way of thinking. In order to generate a real impact on attitudes and habits, environmental education should have, not only more presence in the school curriculum, but more experiential approaches and the implication of school managers.