Teaching kids about the human heart is more interesting then teaching them about other organs, as they can simply hold their chest and feel their heart beating, as opposed to holding their backs and feeling their kidneys working. Demonstrating the intricacy of how the organ actually works is effectively done through a number of kid-friendly experiments.
By rolling up a sheet of paper or using a hollow cardboard tube, kids can make their own stethoscopes and listen to each other's heart beats. Tell kids to pick a partner and place the tube in the middle of their partner's chest. Everyone should be very quiet so they can hear the beat of each person's heart. Add to the experiment by having kids do jumping jacks or run in place. Then they should listen to the other person's heart to hear how their heart beat has increased dramatically.
Tennis Ball Pumping
Take a tennis ball, drill a small hole into it and fill the hollow tennis ball with water. Have kids squeeze the tennis ball numerous times to observe how the water is pumped out of the ball. They should squeeze it until the ball is entirely empty of water. This experiment will demonstrate what the ventricles of the human heart do each time it pumps blood through it and into the rest of the body. Dunking the tennis ball into a bucket of water and pumping it will also demonstrate how the heart pumps blood in and pushes blood out each time it beats.
Different Heart Rates
Record other kids heart rates after they do different things. Measure their heart rates while they are sitting and watching television. Then measure their heart rates after they climb a flight of stairs three times. Next, measure their heart rates when they watch a scary movie. The more measurements of people's heart rates that are done while doing different activities, the more kids will learn about how different heart beats will occur according to level of physical activity. It will also demonstrate how the heart can beat differently based on emotion.