The constructionism is an epistemology that is discussed in several social and educational disciplines. The key thesis is that the human world is based on perception and is a construction of a reality that lies outside of the knowing subject. Everything that can be known of this external reality is created by the observer. The following article describes the tradition of this epistemological position of skepticism and the different perspectives and,,schools" of this constructionist paradigm. Some unsolved questions are discussed, and (...) it is asked whether this paradigm is really new and innovative. The last section concerns the reception of these ideas within the educational sciences and pedagogical practice. (shrink)