I went to a seminar at the University of Denver on the morning after Halloween. There must have been some party - plastic beer cups were scattered along the edge of the road for blocks. (I picked some up to recycle them.)
This got me to thinking - how would it be possible to teach these college students how to put their waste into trash cans that are all over that area? Which begs the bigger question - how can we change our society to teach people responsibility? Many of the parents of these students don't litter, but they were not able to pass that value along to them.