CK-12 Foundation
Ck 12: Biology: Skeletal Muscles
[Free Registration/Login may be required to access all resource tools.] Covers the structure of skeletal muscles and how they move bones.
National Institutes of Health
Nih Curriculum Supplement for Middle School: Looking Good, Feeling Good
A great resource from the Office of Science Education which provides a curriculum for teaching about the musculoskeletal system, the skin system and how they interact. This curriculum emphasizes choices teens can make to ensure good...
US Department of Agriculture
Choose My Plate: Why Is Physical Activity Important?
This site includes a simple list of reasons why getting exercise is important for your physical and emotional well-being. Also, learn definitions and examples of aerobic activities, resistance activities, and stretching activities.
BBC
Bbc: First Aid Procedures
Find out how to treat many kinds of medical emergencies, such as bleeding and bruising, burns and scalds, poisoning and allergic reactions, scene of emergency, respiratory problems, and bone, joint and muscle problems.