This study aims to understand interactions in Korean elementary science classrooms, which are heavily influenced by Confucianism. Ethnographic observations of two elementary science teachers' classrooms in Korea are provided. Their classes are fairly traditional teaching, which mean teacher-centered interactions are dominant. To understand the power and approval in science classroom discourse, we have adopted Critical Discourse Analysis (CDA). Based on CDA, form and function analysis was adopted. After the form and function analysis, all episodes were analyzed in terms of "social distance." The results showed that both teachers exercised their power while teaching. However, their classes were quite different in terms of getting approval by students. When a teacher got students' approval, he could conduct the science lesson more effectively. This study highlights the importance of getting approval by students in Korean science classrooms.