1 ( 9 inch )graham cracker crust
1 (3 ounce) box lime gelatin
2 (8 ounce) containers key lime yogurt
1 ( 8 ounce) tub Cool whip, whipped topping
1/4 cup hot water
Stir gelatin in hot water; let cool. Add remaining ingredients to gelatin. Pour into crust. Let chill overnight.