In 1-quart glass jar, combine water, gingerroot and tea bags. Cover; set in sunny location for 2 to 3 hours or until tea is extracted.
Remove and discard tea bags and gingerroot. In 2-quart nonmetal freezer container, combine tea, concentrate and 2 cups of the carbonated beverage. Cover container; freeze at least 8 hours or until icy, stirring twice.
To serve, spoon about 1/2 cup frozen tea mixture into each glass. Add scant 1/2 cup chilled carbonated beverage to each glass; stir gently.