This article elaborates on a view of human subjectivity as open and intersubjectively constituted and discusses it as a presupposition for student's participation in educational situations. It questions the traditional persistent concept of subjectivity as inner and private, the "homo clausus", which puts self realization before recognition of the other and individual cognition before mutual meaning. From the perspective of "homo clausus" participation is thus limited to mere situated activity. A concept of human subjectivity as open and plural, "homines aperti", makes it possible to conceptualize educational situations relationally and to take the in-between as point of departure for understanding pedagogical relationships. Participation can then be understood in terms of involvement in meaning making, knowledge construction and mutual will formation. The relevance of analyzing discrepancies between concepts in educational theory is that they direct our interest and our attention differently. This is also how theoretical understandings work in the praxis of teaching; teachers' actions are certainly not guided by their theories, but their conceptions about such basic issues as subjectivity and self (what is a pupil?) make some actions and decisions seem more intelligible than others.