This chapter presents the results of a quantitative longitudinal study that examines the assessment of the professional digital competence of pre-service primary school teachers. The study explores the question of how an intervention seminar influences these assessments. The focus is on promoting pre-service primary school teachers' competence in computational thinking and their competence in teaching computational thinking to pupils. This is because pre-service primary school teachers are already challenged to teach pupils digital skills, prepare them for future developments in digitalization, and sensitize them to the effects on learning processes, teaching methods, and everyday life. Educational robotics teaching-learning settings are used in university teaching, by which pre-service primary school teachers expand their competence in computational thinking and train their mediation skills.