Teaching algorithms in upper secondary education: a study of teachers’ pedagogical content knowledge

ABSTRACT Background and Context Computing education is expanding, while the teaching of algorithms is less well studied. Objective The aim of this study was to examine teachers’ pedagogical content knowledge (PCK) for teaching algorithms. Method We conducted semi-structured interviews with seven computer science (CS) teachers in upper secondary education (students aged 15–18). The data were analyzed qualitatively. Findings We found two patterns of variation in teachers’ PCK. First, we detected variation in the teachers’ goals related to their view of algorithms: they either focused on “thinking” about the algorithm as an object, or focused on “thinking and making”, where the algorithm is also regarded as a program. Second, we found variation in teachers’ knowledge about responding to differences between students, which may be generic or topic-specific. Furthermore, our findings reveal that teachers consider class discussions to play a significant role as an instructional method for provoking reflection. Implications Our findings regarding PCK may be beneficial for the development of teacher education and professionalization activities for CS teachers.