In teaching Conceptual and Historical Issues in Psychology (CHIP), it is often assumed that students learn critical thinking by being exposed to it, as if absorbing it through osmosis. Moreover, assessment guidelines tend to consider this ability only for higher marks. The authors of this paper believe, however, that critical thinking should be trained as a central skill: in this contribution, they share their experiences in teaching critical thinking directly. Specifically, they lecture on critical thinking and argumentative writing in a secondyear module that also includes research methods training. Several journal articles are discussed in class, and the exam itself consists of critiquing two research reports. In this course, quantitative and qualitative research are discussed by two different lecturers. However, co-teaching is not framed as a debate: the lecturers aim to avoid both providing a stale compromise and presenting the two approaches as irreconcilable. The authors’ experience with this module supported their initial worries about the osmosis model. Most students were capable of pertinent critical observations on research, arguably because they absorbed this skill from their previous courses. However, integrating isolated comments into a coherent critique was challenging to many, and it took much effort and guidance from the lecturers