I was thinking about the cheerleader costume we made for my daughter a few years back and realized that we probably could have made the pom-poms for no cost with items from around the house... This is the first time I attempted this and I think it turned out pretty well! They even sound like real pom poms!
Just a side note, 1) I used paper scraps since this wasn't actually going to be put to use and 2) I think if you were to do this, Target plastic bags or pretty colored bags would obviously be the best choice. All I had in the house were bags from Hannaford and Price Chopper so that is what I used.
Pom Pom Tutorial
5-6 plastic shopping bags
Paper Towel Tube
Paper, Wrapping Paper or Fabric to cover tube