Amphibian Embryology Tutorial, originally created to supplement Jeff Hardin's Introduction to Animal Development course at the University of Wisconsin-Madison, is "part of an ongoing project designed to implement multimedia and computer-based learning materials in the university undergraduate classroom." The tutorial is organized by major stages of development: Oogenesis and fertilization, cleavage, gastrulation, and neurulation. The Web site also includes an explanation of why we use amphibians to study development. The tutorial presents detailed explanations of each developmental stage and makes generous use of diagrams, photographs, and movie clips. This Web site would be a terrific resource for students wishing to review amphibian embryology outside the classroom at their own pace.