“…And they test a variety of advanced technologies including artificial intelligence (Corbett et al, 1999), networking (Shneiderman, Borkowski, Alavi, & Norman, 1998), virtual reality (Dede, Salzman, Loftin, & Ash, in press), virtual communities, visualization and modeling, and hand-held computers (Pea et al, 1999). They take on challenging tasks related to scaling-up and nation-wide implementation, such as teacher professional development (Corbett et al, 1999;Shneiderman et al, 1998), cross-sector collaboration (Linnet al, 1999;Pea et al, 1999), and commercialization (Pea et al, 1999;Resnick, 1998). And these articles explore deep theoretical issues related to scaffolding and knowledge integration , visualization and the formation of mental models (Dede et al in press;Horwitz & Christe, in press;Kozma, in press;Pea et al, 1999;White & Frederiksen, in press), and technological support for problem solving (Corbett et al, 1999;Schwartz et al, 1999).…”