One online instructor (Alley 1996) has described this changing pedagogical consciousness as an �instructional epiphany�.� Alley tells of a personal transformation, stimulated by online instruction, marked by two "milestones". First, he had to totally redesign his course to fit and leverage the new learning environment. Second, he had to rethink what he calls his �basic approach�: �As long as I held on to the traditional �sage-on-stage� style of teaching, I would keep reinventing ways for students to be a passive audience� (1996:51).� Similar changes in pedagogical belief and practice have been reported by other faculty who have taught web-based courses (Brown 1998; Jaffee 1997; Cremer 1998) as well as researchers who have interviewed online instructors (Frank 2000).�� There are clearly some �structural constraints� built into the virtual classroom ecology that make it difficult to implement traditional modes of delivery and, in this sense, almost force instructors to entertain active learning strategies. As Frank (2000) discovered in her study of online instructors, "All of the participants saw online learning as empowering for students. The most valuable benefits were the facilitation of active learning, critical thinking, collaboration, confidence, and lifelong learning habits. A common theme was the way in which the teacher is forced to give up the control that one has in a face-to-face environment and re-examine the traditional role of content deliverer".� Just as the physical classroom architecture imposes constraints on, and opportunities for, particular pedagogical practices, so too does the virtual classroom. John Seely Brown (2000) has described the environment of the world-wide-web as a �learning ecology� that is a self-organized evolving collection of cross-pollinating overlapping communities of interest.� Asynchronous web-based courses that include a discussion forum possess many of the same ecological features. All members of the class can receive and broadcast information at any time. This critical communication feature distinguishes the virtual classroom from prior forms of instructional technology.�� While instructors can mediate and guide, they cannot entirely control the flow of communication. Thus, instructor and student roles and relations are less hierarchical and more overlapping and interactive. These greater opportunities for participation can contribute to a greater diversity of opinion and perspective. It is hard work to establish these social dynamics in a physical classroom constrained by a fixed space, a designated time block, and trained inhibitions. The virtual classroom, in contrast, has the potential to establish new patterns of instructor and student interaction and, accordingly, different teaching and learning roles and practices (Girod and Cavanaugh 2001; Becker and Ravitz 1999). ��������� In making comparisons between the physical and virtual classroom, it is important to emphasize a cautionary caveat. The pedagogical ecology, be it a physical classroom or a virtual interface, cannot entirely determine a particular pedagogical practice or learning outcome. The pedagogical ecology offers opportunities and constraints that will shape and influence classroom dynamics and learning outcomes, but much will also depend on the principles informing, and the actual design of, the teaching and learning process (see Chamberlin 2001). The various practices that are employed in both a physical and a virtual classroom indicate the range of possibilities. However, if we believe that, for the purpose of student learning, active student engagement and interaction is preferable to the passive reception of information, we should consider the degree to which this principle is advanced or facilitated by the expanding virtual learning ecology.�

have less to do with the proven effectiveness of the particular practice than the desire to appear legitimate or conform to normative expectations.�