In the field of educational philosophy, health and environmental education share many common goals and challenges on the level of curriculum theorizing as well as the level of pedagogical practice. One of these challenges is to develop a radical philosophy of education which is critical and takes a controversial point of departure rather than the one of accommodation. It highlights, in other words, the socially critical role of education. From this point of view some key concepts are discussed in the paper in relation to health and environmental education: democracy as means and end, critical thinking, the critical orientation, and the action perspective. One of these concepts, critical thinking, is elaborated in particular as it is considered to be essential to pupils' development of action competence. A description is given how it can be seen from four perspectives: the epistemological, the transformative, the dialectical and the holistic