This instructable will show you how to make a neat looking and sounding kazoo from PVC pipe, a tee fitting and a plastic bag.
Step 1: Materials Needed
You will need a piece of PVC pipe about ten inches long. I used 1/2 inch, but other sizes will probably work as well.
You also need a tee fitting the same size as your pipe.
Finally you'll need a small piece (about 2 inches square)of a plastic grocery bag.
Step 2: Cut the Pipe
Cut the pipe into three pieces. The sizes are approximately 6 inches, 3 inches and 1 inch. They don't need to be exact. You can cut these with a saw or buy a PVC pipe cutter for about $10 (I'd suggest the cutter).
Step 3: Add the Diaphragm
Take the smallest piece of pipe. Hold the piece of the plastic bag on one end and insert that into the "top" of the tee. Push it down until it's snug but not too tight. You may have to wiggle it around until you get the best sound.
Then add the other pieces of pipe, one to each end of the tee.
Step 4: Playing the Kazoo
Hum into the 4 inch end. The diaphragm should vibrate. If it doesn't, take out the short piece of PVC and try again. If the piece of plastic bag tears, just use another one.
You can make all kinds of variations of this design using different lengths of PVC and different connectors.