Much of the research on constructivist teaching/learning approaches within science classrooms has focused on the roles of the teachers. Issues related to curriculum implementation, pedagogical skills, and the processes of social construction of knowledge have been addressed within this research. This article examines students' perceptions of the changing nature of the classroom as a consequence of the implementation of constructivist approaches. The study was conducted over a 4-year period involving classroom observation of students, interviews, and questionnaires. The classes chosen for observation were taught by teachers who had previously undertaken an intensive in-service program aimed at introducing constructivist approaches into secondary science classrooms. The results of the study indicated that students are not only appreciative of the opportunity to use their own ideas and knowledge but are also aware of the changing roles and responsibilities required of them within the classroom. Although they were willing and confident in becoming involved in the learning process they were more aware of the role of the teacher within the classroom. The results of the study indicate that a clearer understanding of group interactions needs to be developed in terms of developing social construction of knowledge as a more powerful learning approach. ยฉ1997