The sponge game is a tag game for any number of participants (10 or more).
You need one sponge (or a similar object).
One placer is selected. He is dirty and has to be cleaned. To clean him, the other players get a sponge. They have to touch the dirty player with the sponge. The hard thing is: when holding the sponge, they may not move around. They have to pass (throw) the sponge from player to player and then touch the dirty player. Of course, throwing the sponge at him does not really clean him, so that does not solve the task.
Of course, all players MAY move around, they only have to stand still while holding the sponge!
When your dirty player is too fast and can escape the others too easily, you can also play with two (or more) sponges at the same time.