Critical thinking and knowledge construction have become essential competencies for people in the new information age. In this study, we designed an interactive learning environment involving three forms of interaction: individual reflections, group collaboration and, class discussions. The purpose of this study was to investigate the extent to which the three forms of interaction promoted students' critical thinking and knowledge construction. Seventeen students at National Institute of Education of Singapore participated in this study. Their reflections and discussions were analyzed by following a content analysis approach. Results showed that writing reflections had potential to promote critical thinking but, not all students thought critically. Knowledge construction in groups and in class discussions happened at lower levels. This paper presents the conceptual framework, design specifications and evaluation results of the ILE. Implications of the results are discussed. (Contains 1 table and 3 figures.)