This study aims to reveal how and under what conditions a student teacher develops views on lesson evaluation. Observing a student teacher during a two-week teaching practicum in Japan, with a focus on the content of post-lesson discussion, allowed the researcher to model the development of views through the application of the transformative learning theory proposed by Mezirow(1991). Three types of learning were identified, and the conditions necessary for generating that learning were also revealed. This study makes three important suggestions regarding the stimulation of student teachers' transformative learning through post-lesson discussion. The first key is to critically question a premise, such as what and how the lesson was planned. The second key is to present critical or concrete ideas instead of providing ambiguous remarks. The third key is to communicate well to generate the three types of learning. The implications should be applied accordingly with regard to the local context and should be flexible to any situation in international cooperation in education.