Evidence suggests that in the professional education of teachers the moral goals are currently a neglected topic in favor of the subject matter and knowledge. The constructivist instructional approach VaKE (Values "and" Knowledge Education) addresses this problem by combining the moral and epistemic goals through the discussion of moral dilemmas. The main research question of this practice-based study was whether teacher educators can improve their instructional practice by using VaKE. We describe an empirical study of a teacher educator who used VaKE in order to (i) facilitate pre-service teachers to solve moral conflicts which they are faced with in their workplace learning and to (ii) increase the moral climate in his course. 58 pre-service teachers who formed two classes participated in the study. The study consisted of three research phases: In the first research phase the types of the pre-service teachers' moral conflicts were examined. In the second research phase the most frequent types of moral conflicts were used as a basis for an explorative quasi-experimental pre-posttest study. This study investigated the effects of VaKE compared to a traditional case-analysis approach with regard to the pre-service teachers' application of discourse-oriented actions for conflict resolution. In the third phase, a case study method was used comprising a random sample of seven pre-service teachers chosen from each class to investigate the perceived learning climate during the intervention. The results indicate that VaKE provides the possibility to combine the moral and epistemic goals of the professional education of teachers.