Build a Pumping Heart Model

Materials Required:
Small jar or glass
2 bendy straws
Balloon
Tape or glue
Water
Red food coloring (optional)
Sharp toothpick
Steps Involved:
Fill the jar or glass halfway with water and add a few drops of red food coloring to simulate blood. Mix well.
Cut the neck off the balloon, stretch the remaining part, and place it over the top of the jar so it is taut. Save the neck piece for later.
Carefully poke two small holes in the top of the balloon using a sharp toothpick, spacing them about an inch apart.
Insert one bendy straw through each hole, with the bendy parts sticking out of the top of the jar.
Use the neck of the balloon to cover the opening of one of the straws to seal it.
(Optional) Place a cup under the open straw to catch any splashes.
Have your child press up and down on the balloon to simulate the heart pumping. The water will flow through the straws, showing how blood moves through the circulatory system.
Discuss how the model represents the heart’s function and how the straws simulate blood vessels.