Here's an idea to get the competitive juices flowing.
Start saving jar lids - peanut butter jars, pickle jars, whatever. Make a target stand with a simple cross bar about 4' tall and maybe 6' wide. Loop nine pieces of wire onto the cross bar, hanging down about 10" with a hook on the end, preferably pointing away from the shooters. Put it out at 25 to 50 yards and hang a jar lid on each hook.
Now, two shooters step up to the line. At the signal they start loading and shooting, one from the left end and one from the right. At one point per lid, whoever gets to the center first wins. The winner can then "pour it on" and poach into the other shooter's territory. Everybody gets a point score.
If you want to keep shooting after everybody has had a go, do a round robin, highest cumulative score wins.