The present working paper represents an attempt to pursue knowledge-building inquiry through working simultaneously with conceptual and material artifacts; i.e., consider artifacts as hybrid entities embodying meanings as well as physical characteristics. The study is motivated by our effort to avoid overemphasizing intellectual aspects of inquiry by finding a way of simultaneously being both hands on and minds on. The research described in this paper is a case study of a 4th5th grade teachers (Marianne) efforts to create classroom activities and social practices that support progressive-inquiry learning (Hakkarainen, 2003) and creation of a knowledge building community. In this article we will present a knowledge-building project called The Project of Artifacts the Past, the Present and the Future. This collaborative project took place at primary level and contributed to developing understanding of our own culture and diversity of artefacts. The teacher and the students used a networked learning environment called Knowledge Forum. We will first describe basic principles of collaborative knowledge building and progressive inquiry as well as the essential features of networked learning environments such as Knowledge Forum. In this paper we will highlight the teachers role to support students deepening question-explanation process and a shared process of knowledge building through Knowledge Forum. The present analysis relies on teachers structured project diary and video recordings of the teachers interaction with the students and some excerpts of Knowledge Forum database.