Knowledge about sustainability problems as it is typically taught does not "per se" lead to action for tackling these problems. Environmental and sustainability education researchers have argued for teaching more action-oriented knowledge. This article addresses the 'didactical work' required for teachers to do so, both in preparing and implementing lessons. The authors employ transactional didactic theory and the analytical method Practical Epistemology Analysis to open-up the black box of teaching and learning action-oriented knowledge on sustainability issues. The methodology, that has a strong focus on classroom observations, allows to empirically investigate the influence of teachers' actions on students' learning. It is here applied to a case study in higher education where it is engineering teachers' explicit ambition for their students to explore and develop a wider area of knowledge about sustainability issues. Our findings shed light on what this requires in terms of the 'scripting', 'staging', and 'performance' of lessons.