You are manager of Grandpa's Mickey DeeDees, a popular fast food restaurant with a drivethrough.
As manager, you get to set the prices and decide when to have a 20% off sale. Prices are set on the Prices window, accessed from the menu bar. To change an item's price, double-click the price and enter the new price. Sale prices are calculated for you.
The main screen keeps track of what is ordered and the subtotal. When the order is completed, click Total and a 5% tax is added.
Enter the customer's cash amount and his change is calculated for you.
Sound is supported. You can turn off the sound from the Menu. Sound and prices are saved between sessions.
* Uses improved code in preparation for Mountain Lion.
I suppose this has a function for younger children. But otherwise, it is just a glorified calculator for calculating a 5% tax on any given order. I wouldn't even count this as a game. More like a utility.