The video-recorded lessons in the PCK-tests offered possibilities to analyse the
process in the classroom (Jordan & Henderson, 1995). The video recordings were
transcribed as a detailed description of what happened during the lesson from the
beginning to the end. Variation theory was used in the analysis, meaning that the
researchers looked for patterns of variation (Marton, 2014) that made it possible for
the students to discern aspects and understand the content in specific ways.