Today we learned about the lungs and the respiratory system. The lungs give oxygen to our blood. The blood transports the oxygen to our muscles, and collects waste like carbon dioxide to transport back to the lungs. The lungs then get rid of the waste when we exhale. We conducted an experiment to see how strong our lungs are and then discussed ways to strengthen our lungs. The question: How long can you keep the ping pong ball floating in the air using the power of your lungs and a straw?