In e-learning, interaction with audio and video plays a key role in simulating real teaching situation and improving teaching effectiveness. Analysis of interaction solutions in existing virtual classroom show some deficiencies in a two-way synchronized interaction with audio and video. In order to support better use of e-learning in teaching interaction, we put forward a virtual classroom solution to present real teaching situations and to support a two-way interaction with audio and video. In this article we focus on choice of communication protocol, defining of system server, and requirements of hardware and bandwidth in the process of system development. We also bring forth the modeling methods of video avatar entity and its behaviors. In conclusion, a prototype of this virtual classroom is presented and its teaching functions are introduced.