ADD boiling water to jelly powder in medium bowl; stir 2 min. until completely dissolved. Stir in soda, zest and juice. Pour into 9-inch square pan; cover.
FREEZE 3 hours or until firm. Remove from freezer; let stand at room temperature 10 min.
USE spoon or fork to scrape jelly mixture into small pieces; spoon into 6 dessert dishes. Top each with 1 Tbsp. Cool Whip and 1 berry. Serve immediately. Freeze leftovers.