I like to see how many welding rods the apprentice can bend behind his neck.
Spending the whole day with a sweaty back and flux crumbles down your shirt makes for a good hoot.
We send the kids down to the soapstone machine a lot, too. When they can't find it in the basement, we tell them to go ask someone else where they put it. That guy tells him to go ask someone else. Usually each guy is at least 10 or 12 flights of stairs away, or half a mile on the other side of the job.
I've seen a kid burn up a 12 hour shift and 10,000 stairs like that. It's a beautiful thing.