An enterprising pizza restaurant might make this offer:
"If you have an 'A' on your report card, free pizza on Tuesday night. Just bring your parents."
Why would the restaurant make this offer? Because they make plenty of profit on the food and drink the parents order.
Could you make the same offer? Could you partner with your local pizza restaurant?
You would have a captive audience of parents. Why not make a short presentation or give out information about your business? After all, you are the co-sponsor.
My thoughts? If you sold diet products, you could make the same offer: "If you lost one or more pounds last week, free pizza on Tuesday night. Just bring a fat friend and your pizza is free."
Okay, maybe I went a little bit too far, but use your imagination.