I learned that the Florida heat causes rubber bands to decompose and that I should actually refrigerate them. So I bought a bag from Staples and put them in the fridge. Now I can have a dependable rubber band each time. (I used the ones that came on my mail prior to this and they never lasted long.)
The teens write their names on them and then put them around their drink bottles so they can identify their own. When not in use they go on the wrist for use next time we gather. We waste so much less water and beverages b/c each knows his/her container. And the bands are reusable!