This paper reports on the practice of Korean student-teachers who used a high school Japanese textbook to prepare mock lessons for their mock Japanese language classes. Firstly,the cultural framework is lectured based on the three Ps of foreign language standards and the four Cs of CLIL by Professor (author). Secondly, the teacher trainees select from the textbook a culture that can be do in the classroom, and design a cultural experience mock lesson according to the ADDIE model. Thirdly, they revise the mock lesson based on the feedback and comments from peers. Finally, the teacher trainees reflect on the participants’ reflection sheets and satisfaction surveys. As a result of the practice, the cultural experience mock lesson was highly satisfying for both the teacher trainees and the participants, but the practice made the issues visible. In particular, the lack of desk-to-desk instruction became apparent, which led to the realization that it was necessary to teach the importance of desk-to-desk instruction in mock lessons for second foreign language (Japanese) classes as well.