Here's one idea to make a game of picking up trash.
Hunting throwaway cans with a bow and arrow is an enjoyable way to sharpen your target eye, while at the same time picking up trash that mars the beauty of your local landscape. (And, unfortunately, it's likely that careless consumers of canned beverages will always provide you with plenty of "game" to pursue.)
The sport is easy to play. Two archers stroll, side by side, along a can-littered roadway or trail. The first person (designated here as No. 1) to spot an offending beer or soda can calls out, "Target!" Both shooters stop, and No. 1 takes a shot. If a hit is scored, he or she retrieves and bags the container (in a garbage sack, say), tallying one point. If the shot is a miss, the second person advances three paces, takes aim, and lets fly at the can. If No. 2's arrow is also off the mark, it becomes No. 1's turn to take three steps forward and—once again—have a shot. This continues until one or the other nails the trophy. (Naturally, the archer who garners the largest number of empties wins the round.)
The game can be played like horseshoes too, as in "close wins the point." In this variation, the archers stand side by side to loose their arrows. The shooter whose shaft strikes closest to the target bags the can, and is also allowed to take the first shot at the next empty.
Either variant of the contest can be played to a set time limit — two hours, for instance — or until both shooters get tired of lugging cans around and agree to quit. Bets on who will nail the first or the largest number of containers, plus side wagers on who will hit a given target first (for those who enjoy such added "spice"), can enhance an interesting afternoon of litter pickup.
Finally, the sport can become even more competitive when approached as a team undertaking in which pairs of archers carry the contest along different roads and trails, then return to "base camp" to count their booty and hold an awards ceremony.