You are going to create a public service announcement that convinces people they need to exercise in order to keep their heart, lungs and blood vessels healthy.

It will be like writing a television commercial, except that the purpose of a public service announcement is to inform people about a socially important topic, while a commercial tries to get people to buy a product.

You know exercise really does change the way our body works, but you need to find some more facts to share with others. Visiting the following Web sites, and choose what you think are the three most important ideas people should know about the importance of exercise:

American Heart Association Their numbers don't lie—exercise can save your life. It's science!
Physical Activity for Children Another part of the American Heart Association site, this page shows some stuff you can do right now!
Healthy Heart Advice See movie clips of science-expert-person Dr. Joel Posner telling all about keeping a healthy heart.