In order to understand what might be meant by "mathematics education is undetermined", let me start by saying a few words about "mathematics", "mathematics education" and "undetermined".2 I consider "mathematics' an open concept, which, depending on the discourse one uses, might acquire many different possible meanings. In Philosophical Investigations, Ludwig Wittgenstein talks about the variety of language games, and "mathematics' might well be operating as a variety of such games. While mathematics as a research field includes a vast domain of unsolved issues and conceptions in development, mathematics as a school subject refers to a well-defined body of knowledge parcelled out in bits and pieces to be taught and learned according to pre-formed criteria.