The human body functions as a result of the heart muscle pumping blood throughout the organs, tissues, muscles and skin. As children learn about the body's cardiovascular system, they will be able to understand how the heart muscle works much easier if they can see a working model of a heart in action. You can make a heart model out of simple, everyday materials that can be found around the house.
Fill a hot water bottle three-quarters full of water.
Squeeze 10 drops of red food coloring into the bottle.
Insert a clear plastic tube into the opening of the hot water bottle.
Tape the tube onto the hot water bottle with duct tape.
Squeeze the hot water bottle. The squeezing action acts as the pumping action of a human heart, and will force red water through the clear tube as blood is pumped through the veins and capillaries in the body.