$.16 per cup
Variables: weather, mood of people walking by, number of people walking by
Constant: price of lemons, sugar, cups, and ice cubes
Perishables: ice cubes, lemons, sugar
Out of this game I got that I am never buying or going to try to maintain a lemonade stand. When I am old and have kids I will let them try it, but I'm not going to encourage it for a future career. Don't put future students through this torture.