The Doughnut Ring

Jim and his friends are upset to hear that their school janitor's car has been stolen, and just before he's due to retire too. So Jim comes up with a brilliant idea to help raise money to buy a new car- selling doughnuts. They start by making their own doughnuts to sell but run into problems when demand exceeds supply. That's when Jim has another brainwave and decides that the only way to make enough is to write a chain-letter asking people to make more doughnuts. Then the doughnuts start rolling in.and rolling in.