The intervention consists of six interactive sessions using various media (i.e., overhead transparencies, graphics, and three-dimensional demonstrations) to present instructional material. Topics include an explanation of osteoporosis and its modifiable and nonmodifiable risk factors, prevention of osteoporosis via healthy food choices (i.e., high calcium, low fat foods), and prevention of osteoporosis via weight-bearing exercise. Each girl monitors her own progress toward the goal of 1350 to 1500 milligrams of calcium per day. A similar method allows simple self-monitoring of weight-bearing activity. The intervention program is reinforced via monthly self-monitoring for 18 months. The education-only program consists of six generic sessions on healthy eating, physical fitness, and healthy lifestyle choices.