Tie a hula hoop to a rope and string it over something safe above the kids in a tall room.
Divide kids into teams and use a balloon as a ball. Each team tries to get the balloon through the hoop. If you have a big enough room, you can put a hoop at each end.
Make it hard by having someone hold the rope and keep the hoop moving up and down.
The more kids you have, the more balloons you can use, but you might want to color code them.
The best part of this game is watching a kid jump up for a falling balloon and grunt hilariously as he doesn’t even come close to the slowly descending balloon.