We are currently doing Jonah. I made a whale last month -- lots of duct tape and plastic sheeting but it is worth it!!
The whale is used for the Marketplace workshop, but is set up in Fellowship hall once the kids are off in their rooms. In Marketplace they meet one of the sailors from the boat that threw Jonah overboard. The sailor then takes the kids a few at a time to sit in the whale for a few minutes to discuss what it was like, and what could have been going through Jonah's mind. Then they come out and write a "message in a bottle" - what message they think Jonah would have said. Remember, he didn't know he was going to get out!! The younger kids just say "Help!" but the older kids are really showing some great insight!! The notes are photocopied so one goes in their journal and one goes in an empty soda bottle to take home and share with their parents.