Role of the Heart

Role of the Heart


  • Dish pan
  • Empty milk gallon for water
  • Empty smll water bottles
  • Playdoh
  • Plastic drinking straws that bend
  • Toothpicks
  • Paper towels
  • Blood pressure device


Instructions: Using a small bottle, demonstrate pumping water through and empty straw and a dogged straw to simulate issues of cholesterol and damage to arteries.

Start out by providing students with a small empty water bottle, 1 small, and playdoh or modeling clay. Have students will the bottle with water and build a pump as shown in the picture using the playdoh and straw. It is easiest to wrap the straw with playdoh to create the lid.

When complete, the squeezing action forces water through the straw. Collect the water in a bucket, bowl, dish pan, or aluminum pan.

Have students add a small amount of playdoh into their straw. Use a tooth pick to position the “clog”. After creating the plug, have students use their water pump.


Discussion: Fat is a part of diet which can be good for our brain and for energy. However, some fats are better than other for our heart. While many things can cause heart problems, the cholesterol (LDL) found in animal fats is an important contributing factor that we can control through a healthy diet. LDL smears and sticks to the walls of our blood vessels and causes blockages. Good Cholesterol (HDL) found in plants like olives, olive oil, nuts, avocados and fish, for example, help remove LDL from out body.


What is PRESSURE? Give examples of where you might measure Pressure. Pressure is a force on something else. Squeeze an arm or a bottle applies pressure or force. The heart muscle squeezes and that action places pressure forcing blood through the veins and arteries of the body. Common things you might measure for pressure… bicycle and car tires, blood pressure.


How are the two pumps different? How do you think a blockage affects the heart? Have students describe how they worked and describe how they felt different. The clogged required more WORK or PRESSURE to move water through the straw. A clogged artery would require the heart to work harder to more blood though the body.


Download this activity here.

See video tutorial led by AAC STEM Advisor, Karen Meyer here!


Grade Range: PreK-8th grade


Time: 25 Minutes


Synopsis: The heart is about the size of a fist and pumps blood through veins and arteries. In this activity students learn about the action of a pump and the pressure differences between clean and clogged arteries.