||Schools are responsible for developing students’ learning abilities in order to prepare them for the future. However, learning power was rarely explored in previous studies. This study considered classrooms as a proximal level of influences from ecologically-oriented systems theory and therefore centered on exploring the effects of operating classrooms as learning communities (CaLC) on students’ learning power. Learner-centered teaching, which includes the components of inquiry, collaboration, and expression, was used to assess how far CaLC has progressed. It comprises the classroom processes, along with student engagement activities (i.e., inquiry, collaboration, and expression), and classroom social relations. By employing a mediation model, this study aimed to disentangle the effects of classroom processes on learning power. A total of 1478 students from 14 junior high schools in Taiwan participated in the survey. The findings indicate that student perceptions of learner-centered teaching, engagement activities, social relations, and learning power all reached a high-intermediate level. It also found that learner-centered teaching directly affected learning power and exerted indirect effects through engagement activities and social relations. This study contributes to the research on the learning community by providing a more comprehensive analytical framework for detecting the impact of classroom processes. Besides, the three identified components (i.e., inquiry, collaboration, and expression) of CaLC can be a practical guide for the instructional practice of learner-centeredness.