1. Bring the 3 cups of water to a boil; add the three boxes, mix constantly with a whisk. Return to a boil and boil for two minutes. Remove from heat and cool completely.
2. When completely cooled, fold in the container of Cool Whip using a whisk. Then add in the mandarin oranges and crushed pineapple. Make sure that both cans of fruit have been completely drained before adding.