You can build a guitar that works great from a simple cigar box. This isn't the elaborate real stringed guitar that some people can make, but a simple rubber band guitar.
This is a great idea for just playing around or showing the kids, and they will absolutely love having a hand made cigar box guitar to play with.
If you like this, you can later decide to learn how to build an elaborate cigar box guitar. Here's how you do it.
First you will cut a hole in the bottom of the cigar box. It doesn't have to be very large, just three inches or so across. You can use a box cutter to do this, but be careful.
You will then poke four or five holes on both sides of the hole where you will insert the rubber bands. Make sure the holes are poked in a straight line.
You can trace a line with a pencil and a ruler if you want to be sure that the rubber bands will be exactly straight. You want to take five rubber bands, and cut them so they are one line instead of a circle.
The next thing you want to do to build a cigar box guitar is put one end of the rubber band through the hole. Tie a large knot so that the band won't slip back through.
Then you will stretch the rubber band to it's corresponding hole on the other side of the circle. You will put that end of the rubber band through the hole and tie another knot.
You can make the rubber band tighter or looser, depending on how you want the guitar to sound.
If you don't like this method, you can check out different ways at http://www.buildaguitar.net
To build a guitar that sounds very different with each band, make the rubber bands all different as far as how tight they are. Then you will cut off the extra rubber band on the inside of the box.
Then you can glue or tape the box shut. With a little extra imagination, you can add a handle, and paint the guitar so it will be your very own.