In this paper, we discuss the extraction of relations between lecturer and students in lectures by using multi-layered neural networks. Here, the relations among a few features concerning on the behaviors of the lecturer and students can be represented by multi-layered neural networks with the time-delay. Furthermore, we introduce a structural learning algorithm with forgetting for neural networks for the extraction of rules in the interaction. The above time-series models are analyzed focusing on weights in multi-layered neural networks. Concretely, we analyze which lecturer's behaviors (face and hand movements and loudness of speech) give great influences on behaviors by students (face movements). On the contrary, we analyze which student's behavior (face movement) give great influences on behaviors by lecturer.