Air horns are extremely loud. That's why they're used by truck drivers, fire trucks and ambulances to clear the way in a hurry. This video will show you how to make your own air horn, using stuff you've probably already got in a junk drawer.
A pill bottle with a hole in the cap and bottom
1. Cut two pieces from the balloon and stretch them across the top and bottom of th pill bottle, securing them in place with the rubber bands.
2. Make a hole through the balloon on the bottom of the bottle, just big enough to insert the straw through.
3. Make a hole in the side of the bottle.
4. Blow through the straw to make a terrible racket.