Paper Bag Lungs
Ages 2 and older

As we focus on getting fit this January, let’s learn about how our bodies work.  Today, we are talking about our lungs. As part of the circulatory system, they work hard to help oxygen enter our bloodstream. They also help us get rid of carbon dioxide. Cells produce carbon dioxide as a waste product, and that goes into our bloodstream so it can travel to our lungs. As you breathe out, you expel the carbon dioxide that was in your lungs. Exercise, healthy eating and watching out for air pollution can all help us keep our lungs working their best.

Our lungs are also one of the organs that it is easy to observe. Just like this model, children will notice their chest and abdomen fill with air as they take a deep breath. Connecting our scientific model to other evidence is a great way to think like a scientist.


  • 2 lunch size paper bags
  • 2 straws
  • Tape
  • Pen or other coloring supplies


  1. Label the bags, left lung and right lung. This is a good chance to teach kids that they have a lung on either side of their body.
  2. Draw lines on the bags, starting at the top of the bags and branching out to reach the bottom. They should look a little like tree branches. These are the bronchioles, which are tiny air tubes.
  3.  Draw a sac on the end of the bronchioles. These are the alveoli, and they are where oxygen and carbon dioxide get exchanged
  4. Insert your straws, putting one in each bag.  Put the straw into the bag so that almost half the straw is inside the bag
  5. Tape the straw inside the bag, making sure the bag doesn’t have air inside of it
  6. Blow into the straws-the bags will inflate!

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