Caps for Cats/Pops for Pups

I am trying to raise money for our local animal shelter, which anyone could do for their local animal shelter. I volunteer there and it has grown dear to me, and sometimes there isn't enough money to provide these animals with everything they need. Now, we aren't the kind of people to just sit back and watch the problem, we will rig something up to fix it temporarily, but I would really like to start a campaign that collects plastic bottle caps and metal pop tabs and turn those in for money to donate to our animal shelter and other animal-based groups.