The purpose of the present paper was to examine three generations of research on technology-mediated learning carried on by the present investigator's research group. The first generation focused on examining computer-supported collaborative learning from the cognitive perspective. The main focus was to examine to what extent knowledge-seeking inquiry elicited conceptual change. Problems of transferring inquiry learning culture from one country to another pushed us to examine social practices and other participatory aspects of learning that had been invisible to cognitive researchers. The second-generation research focused on analyzing patterns of participation in computer-supported collaborative learning. The emerging third generation research aims at overcoming the dichotomy between the cognitive (knowledge acquisition) perspective and socio-cultural (participation) perspective by means of long-standing and deliberate efforts of knowledge-creation, involving what is called "objects of activity." Theoretical and methodological implications of the generations are discussed.