When I took gym as a freshman in high school, our class was 1 hour and 15 minutes long. We typically started class with a 10 minute run around the gym. Many people cut corners or raced each other as we jogged around the gym. After we finished running, we participated in a variety of sports including: soccer, basketball, volleyball, badminton, tennis, flag football, dodgeball, and a few made-up sports related games. These sports alone gave the class a good dose of exercise. Thats what I did anyway and students did not want to participate or try hard when it came to plain exercising because it was too boring. Sports liven up the class a lot more.