Capture the flag
Put something in a box, f.x. a jacket. Thats the flag.
Split the participants into 2 teams. One team has to defend the flag, and the other team has to get close enough to touch it (to capture it).
The attackers has a glove or a clothespin somewhere where it can easily be seen and removed from. The attackers can only attack while carrying the mark. The defenders must try to keep the attackers from capturing the flag by blocking their progress and by removing the mark.
If any attacker loses their mark they have to return to the home base to get a new (place another box somewhere with a lot of gloves/clothespin in).
Both teams gets a flag, and now has to capture the other teams flag while defending their own.