Rock Paper Scissors with two big teams and an element of tag thrown in.
On a large playing field, split the group into two teams. Make sure there is a halfway point that is recognizable. In the back of each team's side, make sure there is another "end zone" area that is recognizable.
Teams will huddle up and decide which of the rock, paper scissors moves they will do. When both teams have decided, they approach the center line and with the help of the facilitator, they all say "Rock... Paper... Scissors... shoot" together and perform their action (it can be fun to have the actions much bigger than normal - such as their whole bodies turning into rocks, or giant scissors, or big pieces of paper).
Whatever team wins can immediately begin chasing the other team, attempting to tag them. The team that lost tries to run back to their "end zone" as quickly as possible. If they make it there without being tagged, they are safe. If they get tagged, they must join the other team.
The game usually does not end up with one team having everyone and so the facilitator must use his or her discretion of when to end the game.
The 3 rock, paper, scissors moves are:
Rock beats scissors. Scissors beats paper. Paper beats rock.
Compiled & designed specifically for you by Jon VerLee