How to Make a Toy Stethoscope
- 1). Fit small funnels into each end of a piece of plastic tubing.
- 2). Tape around the base of the funnels with duct tape to securely hold the funnels in place.
- 3). Blow up a balloon to encourage the material to stretch. Let the air out of the balloon.
- 4). Cut off 3 inches from the open end of the balloon. Stretch the balloon over the open end of one of the funnels. Secure the balloon covering by taping it around the edges to the funnel.
- 5). Place the funnel with the balloon covering on someone's chest, near the heart. Listen through the other funnel to hear the heartbeat.
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