This qualitative study was conducted with the purpose of exploring the key factors that promote teacher learning. Students took remote classes due to the spread of COVID-19 in 2020. These teachers saved students from learning deficits through active community learning and classroom practice. We observed the community learning experiences of 6th grade teachers at Y Elementary School in Korea for one year and interviewed them. We collected interview transcripts, observation diaries, public documents and class materials, researcher diaries, and SNS conversation records. As a result of the study, the factors that promote teachers' learning are 'collaborative fellow teachers', 'ready-to-use instructional materials', and 'positive students' responses'. In light of the three key factors and sub-factors found through the study, the following topics were discussed. First, the importance of peer teachers in teacher learning and the specific role of leadership. Second, the need and availability of learning materials and rethinking the teacher training system. Third, the presence of students as a factor that promotes teacher learning. Fourth, the aspect of learning motivation obtained from the growth experience of teachers. In addition, it is suggested that teachers are the main agents for improving the quality of school education and solving school problems, and this suggests that success can be achieved based on teacher learning.