Abstract
There has recently been significant emphasis placed on environmental education through, for example, the UN’s Decade of Education for Sustainable Development. Despite this, there is still considerable debate within the literature as to how the aims of environmental education can be achieved within schools. It seems likely that if there is a lack of agreement as to what education for sustainable development should include, then this will impact students’ understanding of sustainable development. This paper presents findings from research investigating how one class of 12‐ to 13‐year‐old geography students in the UK understands the concept of sustainability. The research used concept‐mapping and semi‐structured interviews to explore the students’ understandings of sustainability, within a case study framework. The substantive findings of this research suggest that there is a wide variety of understanding of sustainability among the students, but that generally they allude to three: the nature, purpose and timescale of sustainability. The paper also considers the impact of method on researching students’ subject understandings, in particular the use of context when considering abstract concepts, such as sustainability, and the different results obtained when conducting interviews versus concept maps.