You will need: approximately 30 bags of stones or conspicuous stones, cones or other markings, a large area to play in.
Hide the bags of stones in the playing area. In the middle, create a stone collection point. Split the group into two teams. In each team, decide who will be the catchers and who will be the seekers (you will want slightly more seekers than catchers). The teams and roles are marked. The seekers must find the stones and carry them to the collection area (without hiding them). The catchers can stop the seekers by tagging them. If you are tagged, you must drop your stone and run to the referee, where you must wait for 1 minute before being allowed back into the game. Seekers may only carry one stone at a time, and only those with stones in their hand can be caught by the catchers. When all the stones have been brought to the collection point, the team with the most stones is the winner.