Have campers sort themselves into groups based on their opinions on simple topics.
For instance, ask campers to split into ‘favorite toothpaste’ groups.
Campers might sort themselves into ‘Crest’, ‘Colgate’ and ‘Don’t care’ groups.
Try asking about house pets, (cats, dogs, fish, none,) pizza toppings, favorite colours, etc.
This can also be used to split campers into groups for a game: just keep asking new questions until you have the number and size of groups you want.