Prepare a self adhesive label or post-it note for each young person in your group. Write on it the name of a well-known or famous person. This can be an historical character or current sportsman, musician, TV personality, celebrity etc. Have a good mix of men and women. Keeping the names hidden, stick the post-it notes on the foreheads of everyone in the group. They must then ask questions of the others to find out their identity.