Recent research shows that, as students interpret the demands of the assessment tasks, they vary their approaches to learning in order to cope with the assessment tasks. Three research questions are central in the present paper: (1) Do students who participate in a constructivist learning environment change their perception of assessment demands towards more deep level demands? (2) Do students in a constructivist learning environment change their approaches to learning towards a more deep approach to learning? (3) Is there a relation between change in approaches to learning and change in the perceptions of the assessment demands? Students following the course "Education and psychology" of the teacher training program at the University of Antwerp completed questionnaires during the first, the second and the final lesson of the course. One questionnaire measured their approaches to learning and the other their general perceptions of the assessment demands. The course "Education and psychology" can be labelled as a "constructivist learning environment" with congruent assessment methods. Results of the paired sampled t-tests indicated that students indeed do change their perceptions of assessment demands towards more deep level demands. However, the results also indicated that students did not change their approach to learning towards a more deep approach. On the contrary, students seem to develop more surface approaches to learning during the course. Correlation analyses indicated that only changes of perceptions of assessment demands towards less surface levels are significantly related to changes in approaches to learning, towards a more surface approach. Results of the stepwise multiple regression analyses indicated that students' approach to learning at the beginning of the course seems to have a higher impact on the extent to which they change their approach to learning than how students perceive the demands of the assessment within the course. These results point us to the complexity of the relationship between the learning environment, the students' perceptions of assessment demands, and students' approaches to learning.