Many studies have tried to determine the most important factors in the acceptance of e-learning systems by students thanks to existing information systems (IS) models such as the technology acceptance model (TAM) [1] or the unified theory of acceptance and use of technology (UTAUT) [2]. However, such studies have little, if any, interest towards the social interactions that can also have a great impact on the students' perception of e-learning designs or the students' motivation to learn by using e-learning systems. Yet, social interactions that occur inside and outside the classroom are important in the learning process [3]. Schematically, these social interactions can occur among students, or between students and teachers. While the latter have almost no regulation power on interactions among students, they can control how they interact with their students. This theoretical piece of paper aims to go beyond traditional research that is focused on the technological dimension of e-learning systems by re-introducing the influence of the social interactions between the teacher and the students in the context of blended learning. To do so, it is suggested to rely on the concepts of dialogue and structure that were proposed by Moore [4]. Dialogue "describes the interaction between the instructor and learner when one gives instruction and the other responds" [4]. Thus, dialogue can be face-to-face or distant thanks to ICT (Information and Communication Technologies). Structure refers to the "rigidity or flexibility of the program's educational objectives, teaching strategies and evaluation methods" [4]. The theoretical framework proposed in this paper suggests that in a blended course: (1) both dialogue and structure may influence the quality and quantity of the interactions between students and the teacher; (2) that the technological means used to favor the students-professor interactions may moderate the influence of dialogue and structure; and that accordingly (3) the quality and quantity of these interactions may influence the students' motivation to learn.