This thesis examines how pupils in the upper level of compulsory school learn about environmental issues and related theoretical concepts in an instruction employing an investigative approach and thematically organised content. The results of the study give reason to question some central arguments supporting these designs of instruction. Additionally, and primarily, these results contribute to research on concept formation. An understanding of pupils’ difficulties in learning theoretical concepts as a problem of contextualization is derived, representing an alternative to the influential view in which pupils’ difficulties are seen as a problem of conceptual change.

Three case studies carried out within the pupils’ regular instruction are presented. The empirical material consists of recorded conversations, observational notes and the pupils’ own written material.

The first study shows that the pupils experience difficulty in distinguishing among the different meanings attached to individual concepts in various conceptual contexts. This implies that pupils are often unable to identify the meaning relevant to the specific environmental problem on which they are working. The second study shows that the pupils do not make the connection between theoretical concepts and practical activities, as intended in instruction. Instead, they interpret the concepts within separate practical contexts, i.e. interpretative contexts other than the theoretical contexts. Finally, the third study demonstrates that the context for a pupil’s investigation changes as the pupil’s values concerning the environmental issues are brought to the fore. Thus, the outcome indicates that contextualization is a main factor in pupils’ learning of theoretical concepts. It is shown that the pupils’ understanding of theoretical concepts is dependent on their contextualizations of these concepts, both with regard to different conceptual contexts and with regard to different levels within a context. It is also demonstrated that emotions play a part in pupils’ learning by determining into which context pupils choose to enter.