These sites explain how the skeletal system works. Learn about all the bones that make up the human body. Includes many photos, X-rays, and diagrams. There are some online quizzes and presentations, plus interactive tours of the body.
Click on the skull for an interactive skeleton that allows you to click on the bones that you would like to know more about. Under this interactive skeleton, there are also links to topics such as bone cross section and broken bones.
This page descibes the structure and composition of bones. Very easy to understand with lots of color photos. At the end of the page, click on the "Next" arrow to learn more about the bones and to see photos of a bone biopsy.