Try this. A few years ago, I did this in a kids game. Whenever someone in the stands yelled a stupid comment regarding rules, I yelled back, "THAT'S ONE", then "TWO', then "THREE" and so on. At halftime I was up to "TWENTY-FOUR". During that break, I addressed the bleachers and said, "If your wondering why I'm yelling out numbers, I'm counting the number of comments I hear from people who obviously don't know the rules. I hope we can get to 35, since that would be a new record. Thanks for all your help so far."
Amazingly (or not), I heard about 4 or 5 more.
Believe it or not, after I addressed the crowd, my partner asked me if the record was really 35, because he's had games with lots more than that. The weird thing is, I wasn't sure he was kidding.
