Science Experiments for Kids

Stethoscope Project (Check Your Heart Rate)

What you'll need:

 A balloon

 A piece of tubing

 2 small funnels

 Scissors

 A timer

 Rubber band (optional)

 A calculator (optional)

Instructions:

1. Take the piece of tubing and fit a funnel to each end.


2. Stretch the balloon by blowing it up and then letting the air out.


3. Cut off the top third of the balloon with scissors.


4. Stretch the top third of the balloon tightly over the open end of one the funnels. If
   necessary, use a rubber band to hold it in place.


5. Stir the mixture again with your fork and look at the long strands of gunk that have
   formed.


6. As the mixture cools slowly add more water, small amounts at a time.

Making your stethoscope work:

1. Find your heart with your hand by feeling where it beats in your chest.


2. Sit down somewhere quiet and place the end of the funnel with the balloon over it
   against your chest, directly onto your skin, just to the left centre.


3. Hold the other funnel to your ear. You should hear a low beating sound.


4. Use the timer to count how many beats you hear in 20 seconds. Multiply this
   number by three (use a calculator if you’re not confident) to find out how fast your
   heart beats in one minute.


5. Try doing some more tests such as running around for 5 minutes and then checking
   how fast your heart is beating. Compare your results to your brothers, sisters,
   parents and even pets heart rates, are there any differences?

What's happening?

Did you know that when a doctor listens to your heartbeat with a stethoscope, they are
actually listening for two sounds? The first sound is a longer, lower pitched sound. The
second is a shorter, higher pitched sound.