Bring the sugar and 3 cups water in a saucepan to a boil over high heat.
Boil for 5 minutes; remove from heat and let cool.
Combine the sugar syrup, bananas, orange juice, pineapple and the three 6-ounce cans of water in a bowl or pitcher and mix well.
Pour evenly into two 10x14 baking pans or dishes.
Thaw to a slush before serving by letting it stand at room temperature for 2 hours or for 8 to 10 hours in the refrigerator.