One chilly July afternoon, five high school biology teachers were energetically discussing how to design an animation that would best portray the complex process of blood sugar regulation in the human body. Dale Muzzey, a biophysics graduate student and animator, stepped in occasionally to provide guidance on what Macromedia Flash software could and could not do well. With his support they hit upon a workable interactive model. Then the teachers turned their attention to the task of finalizing the content. How much detail would they include? What level high school class would they...