<p>This paper explores the intersection of emotions and stance-taking in teacher–pupil interactions in science classrooms, with regards to the co-construction of SocioScientific Issues. Drawing from linguistic ethnography, stance-taking models and emotion frameworks, this study examines how anxiety is negotiated in interactions on topic emotions after class. Using data from two Belgian teachers’ afterclass interactions with pupils, the study highlights the co-construction of emotion through stance-taking. In particular, it is shown that teachers' emotional support and engagement strategies can serve as a counterforce to negative emotions elicited by challenging science topics. Conversely, teachers can negotiate anxiety in an unsuccessful way by not addressing the emotional discourse itself. A comparison of interactional (dis)alignment can bring to the forefront these specific strategies that are used in the negotiation of anxiety after a science class. This work contributes to the field of emotions in science education and emphasizes the need for further investigation into the emotional dimensions of teacher–pupil discourse.</p>