At this time, scheduled asynchronous online courses offer the greatest potential for most professional development applications. When multi-point audio and video becomes feasible and low cost, we may want to revisit this conclusion, but even then good asynchronous collaborations may continue to be the core of most online courses. To make the terminology less intimidating, we use the term "NetCourse" to refer exclusively to a scheduled asynchronous online course. This design is particularly valuable for teacher professional development for the following reasons:

Any time. A teacher can use the network at any convenient time: early morning, late night, after school, or on weekends. The duration can be quick snatches at odd times or long, late-night sessions. Emergencies, unscheduled interruptions, odd vacations do not interfere. Conversations do not have to be scheduled. Cross-time-zone communication, difficult to arrange in real time, is as easy as talking to someone across town.

Any place. The participants do not have to meet. That means they can be anywhere. We can have Native Americans in Alaska collaborating with their peers in New York City. International sharing is feasible. Individual teachers can log on at school, home, the library, or from their hotel when traveling. We can also bring the best NetCourse faculty from anywhere in the world and put together faculty teams that include master teachers, researchers, scientists, and experienced professional developers.

Group collaboration. Electronic messaging creates new opportunities for groups to work together, creating electronic conversations that are thoughtful, responsive, and far more permanent than voice conversation. With help from electronic "moderators" these groups can be powerful learning and problem-solving environments. In NetCourses, these groups can be roughly equivalent to seminars or discussion sections in a lecture course but can have a different, more "chummy" atmosphere.

Group participation. NetCourse faculty are particularly enthusiastic about the ability of this design to allow all participants equal time and space to carefully think through and construct class contributions before submitting them. This is especially important for participants who are shy or intimidated in a normal professional development environment.

New educational approaches. Many new options and learning strategies become economically feasible through NetCourses. For instance, the technology makes it feasible for teachers to learn from the best faculty in the world while school is in session, possibly working with peers. NetCourses also can provide unique opportunities for teachers to try innovations in their own classes during the academic year with the immediate support of electronic groups and expert faculty.

There are some very poweful examples of NetCourses serving the needs of educators. For mathematics and science professional development online, two well-established projects are the National Teacher Enhancement Network (NTEN) based at montana State University: and the Mathematics Learning Forums offered by Bank Street College of Education. A survey of all kinds of NetCourses can be found at the Concord Consortium site.

Of course, there is a convergence of technologies and the best solutions may often involve hybrids of unscheduled and scheduled as well as synchronous and asynchronous technologies. On the Internet, audio and video can increasingly be delivered both synchronously and asynchronously. These online technologies will also be combined with "real" or face-to-face meetings to achieve specific course objectives. For instance, it is often important to start a learning group with trust-building activities so participants will be willing to take intellectual risks later on. There is a general feeling that face-to-face meetings or a multi-way video conference are the quickest, most reliable means of building the required trust.

Another kind of mixed strategy will become possible when hundreds of participants can enroll in the same online course. If the course is unscheduled but broken into short modules, there will be enough participants at any time to form an asynchronous discussion group for one of the modules or to hold a synchronous virtual meeting. In these cases, the convenience of an unscheduled course could be realized while keeping the advantages of learning in groups and live interaction.

My group at the Concord Consortium developed a unique online course called INTEC (the International NetCourse Teacher Enhancement Collaboration) that combines scheduled asynchronous activities with bi-weekly face-to-face meetings. This design was determined directly by our goals and audiences. The INTEC NetCourse is designed to assist secondary math and science teachers who want to offer increased use of student inquiry as a learning strategy. The change from traditional teaching to inquiry-based teaching is a large step, and the literature suggested that such a change needed local support. Local study groups have proven valuable in staff development, so we decided to support study groups as part of our design. We require at least four teachers enroll together and then meet together at least once every two weeks.

While mixed strategies might offer advantages in certain situations, a "pure" NetCourse can also be a powerful strategy. A key part of our Virtual High School is a NetCourse for teachers called the Teacher Learning Conference (TLC). This NetCourse is a rigorous, 125-hour graduate level course on how to design and offer NetCourses for secondary students. Because VHS teachers were drawn from schools throughout the country, usually one per school, a pure NetCourse using an asynchronous format with no face-to-face meetings was the only feasible alternative. The TLC is very successful and reliably generates a very cohesive, dedicated group of teachers.

Online courses permit us to rethink the role of the faculty in learning and seem to promise economies of scale. There are important savings, but not from changing the ratio of participant to faculty.

Significant savings can be realized through professional development delivered through NetCourses. Because there are no substitute teacher, transportation, room, and board expenses for the participants or the faculty in NetCourses, the costs for high-quality instruction are much lower than traditional approaches. There is the potential of scaling NetCourses up to reach national audiences at one-half the cost of summer institutes.

Many of the faculty teaching online courses report that online courses require more of their time than traditional courses, even with only a handful of students. This would suggest that lower and more expensive participant/faculty ratios are needed for NetCourses. In every case we have studied in which this is a problem, however, the professor offering the online course has created a bottleneck by putting himself or herself at the center of the conversation; most of the messages were between participants and faculty member. This as a major pedagogical and design weakness of much of current practice. Relying on online discussion groups in the NetCourse design is essential, because the vast majority of the conversations can take place between peers in these groups. Each group will need to be monitored by the faculty or moderator. This removes the bottleneck of expecting faculty engagement in all conversations while still providing faculty with manageable feedback. As a result, participant/faculty ratios for NetCourses can be similar to those in regular courses.

NetCourses and virtual schools will soon spark an educational revolution that will have a far-reaching impact. NetCourses will free education from the monopoly of place, creating a free market of courses and educational services. There will soon be thousands, perhaps hundreds of thousands of NetCourses of every size and rigor, addressing every conceivable topic. As a result, education as a whole and the nature of public education will never again be the same.

The transformation of education into a free market could be accompanied by great confusion and many abuses. The most troubling problems will be fraud and inferior quality. If anyone can offer an online course, then the market will be flooded by netjunk: courses that either do not exist or are of inferior quality, or use teachers who are inexperienced or poorly educated. It will be very tempting for the unscrupulous to create a Potemken Academy, an educational facade that looks and sounds impressive but lacks substance.

This problem will have to be addressed the way any free market protects consumers, through a combination of evaluation, accreditation, and consumer awareness. Fortunately, the 'Net is an information rich medium, so it can be easy for a consumer to find out about a course and its teachers. Teacher credentials, records of past courses, expert critiques, and evaluations by prior students can be available for prospective students.

The best solution to the problem of quality is for the education profession to formulate and propagate a set of voluntary NetCourse quality reporting standards. This solution shifts most of the responsibility for evaluation to the NetCourse provider in much the same way that financial auditing standards shift the burden of accounting to companies. The profession still needs to spot check adherence to the standards, but it would not have to undertake a huge evaluation effort.

Once a good self-policing program is in place, NetCourses will be poised to make a major contribution to teacher professional development. It will soon be commonplace for most teachers to be engaged in rich, online continuous learning communities.

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