In the last two decades some researchers have been using elements of Critical Theory to rethink the aims and the possibilities of school mathematics. The field known as critical mathematics education has become an important research area, and has been informing teachers who felt the need to change their practices. In this article, we explore the problems felt by a teacher when bringing topics of critical mathematics education into her classroom. These problems illustrate what we argue to be a domestification of the notion of critique, and offer us a window into the entire contradiction of schooling.