In this paper, we explore the development of practical knowledge of students through experience-based activities such as student teaching and school assistance in elementary schools. Four students, taking the teacher training course of our university, are research participants and have engaged activities as student teachers and school assistants, intermittently spanning three years, in municipal schools of Fukuyama City. We try to describe the cases representing practical knowledge of the students, based on analyzing narrative data which was collected by focus group interviewing with them. Comparing between the cases, our findings are summarized as follows:（i）Practical knowledge of the students is similar in that they have difficulties leading children collectively and feel to succeed in interacting with a child individually,（ii）however, their practical knowledge is distinguished with each personal characteristic of a sign of the practical rule, a connection to the preceding experience, an attempt based on the observation, and a focus on the practical judgment.