This study aims to examine the development of the guidance teacher when instructing a student teacher. This year, we have aimed to clarify the relative improvements in the teaching practice of both the guidance and student teacher as well as to understand the needs of the student teacher and to explore the teaching methods being taught to student teachers. We hypothesized that the explanation of teaching methods by the guidance teacher was dependent on the willingness of the student teacher to learn. Our approach to the study involved analyzing the relationship between the student teacher and the guidance teacher at three stages (at the beginning, in the middle, and at the end of the training). The following three points were revealed as mechanisms for synergistic improvements in teaching practice to occur between the student and guidance teacher: (1) the establishment of clear aims by the guidance teacher in relation to teaching practice, (2) the exploration of a range of teaching methods by the guidance teacher in accordance with the willingness of the apprentice to learn, and (3) the creation of opportunities for discussion by the guidance teacher.