The Kiddie Stock Market
With the stock market in turmoil, go grab three cute school kids, give them each $100, and marry them up with a financial trader in your market. Introduce the teams to the audience on a Monday. Tell each team they must day trade for one week (they have to buy/sell at least one stock each day). Check in with them daily. Whatever money the kids have left the following Monday they get to keep for school clothes and supplies.