We called our 'changee for a change'. We are also in the process of raising funds for a playground ($37,000 out of $100,000 already since October) and we used old plastic mayo jars. We did not use the really big ones in the classrooms, because the children like to see them fill up quickly. We then take the jars out of the classrooms once a week and empty them into a really large glass pig that sits in the office. Once a week, usually on Friday, it is announced on our school PA how much money was raised by the childrens change.
Something elseyou could do is go to your local dollar store and purchase small garbage pails with lids. (the kind that sit on a desk) These can also be decorated.