HALVE 6 of the cookies; reserve for garnish. Coarsely crush remaining 10 cookies; set aside.
PLACE marshmallows in large saucepan. Add water; cook on medium heat until marshmallows are completely melted, stirring constantly. Remove from heat. Stir in strawberries and lemon zest. Refrigerate 30 min.
ADD 1 cup of the whipped topping to strawberry mixture; stir with wire whisk until well blended. Alternately layer strawberry mixture and crushed cookies in 6 (6-oz.) parfait glasses, beginning and ending with strawberry layers. Refrigerate at least 1 hour. Top with the remaining 1/2 cup whipped topping and reserved cookie halves just before serving.