1 graham pie crust
2 containers yogurt (your favorite flavor)
1 lg. Cool Whip
Fresh berries (raspberries, strawberries, etc.)

Mix yogurt and Cool Whip until well blended. Put in graham pie crust and freeze (covered). For variety, small pieces of fruit can be added to yogurt mixture before freezing. Top pie with fresh berries and spoon of whipped topping to serve.