Abstract Background Over-testing of patients is a significant problem in clinical medicine that can be tackled by education. Clinical reasoning learning (CRL) is a potentially relevant method for teaching test ordering and interpretation. The feasibility might be improved by using an interactive whiteboard (IWB) during the CRL sessions to enhance student perceptions and behaviours around diagnostic tests. Overall, IWB/CRL could improve their skills. Methods Third-year undergraduate medical students enrolled in a vertically integrated curriculum were randomized into two groups before clinical placement in either a respiratory disease or respiratory physiology unit: IWB-based CRL plus clinical mentoring (IWB/CRL + CM: n = 40) or clinical mentoring only (CM-only: n = 40). Feasibility and learning outcomes were assessed. In addition, feedback via questionnaire of the IWB students and their classmates (n = 233) was compared. Results Analyses of the IWB/CRL sessions (n = 40, 27 paperboards) revealed that they met validated learning objectives. Students perceived IWB as useful and easy to use. After the IWB/CRL + CM sessions, students mentioned more hypothesis-based indications in a test ordering file (p