We've made harmonicas, xylophones, flutes, guitars, etc., but never a trombone. This quick experiment is surprisingly simple and awe-eliciting.
What You Need
An empty bottle
Plastic drinking straw
What to Do
Fill the bottle 2/3rds full of water. Place the straw in the empty bottle. Now hold the straw in place with one hand, and blow across the top of it.
Move the straw up and down while blowing, the tones you make are higher and lower pitch, similar to a trombone.
How Does it Work
As you lift the straw out of the water, you are lengthening the column of air inside it. This is exactly how a trombone works.
This awesome experiment came from the book 365 Simple Science Experiments. Check it out!