Distance education has been an important research issue of multimedia computing and communication. Since the instructional activities are implemented on cyberspace, how to control behaviors of students and to increase the degree of communication awareness have been a challenging issue. We propose a system based on the scaffolding theory. Behaviors of students are supervised by an intelligent control system, which is programmed by the instructor under our generic interface. The interface is built based on virtual reality and real-time communication technologies. Students and instructors have their individual avatars that are controlled by a video game like navigation. Those behaviors that violate virtual campus regulations are detected and interceptive actions are performed. The proposed system is implemented on a Windows system and can be used for general purpose of distance education.