The document discusses how Web 2.0 technologies like social bookmarking, blogging, wikis, podcasting, photo/video sharing, and collaborative documents can be used to create collaborative learning environments within and across classrooms. It provides examples of how these tools are being used by schools and teachers, and encourages readers to try creating their own class wiki or using tools on Google sites. Challenges of connectivity, internet safety, and linking activities to curriculum goals are also addressed.