Turn lemonade into chewy, bouncy, lemony fruit snacks thanks to the magic of gelatin!
In medium microwave-safe bowl, combine thawed lemonade concentrate, lemon juice, and sugar. Sprinkle gelatin over surface of liquid. Use rubber spatula to stir until no large lumps remain. Let mixture sit for 5 minutes.
Heat lemonade mixture in microwave for 1 minute. Stir mixture. Heat in microwave until mixture bubbles and foams, about 1 more minute.
Use oven mitts to remove bowl from microwave (ask an adult for help—mixture will be VERY hot). Stir mixture until fully combined and smooth.
Place lemon slice molds on rimmed baking sheet. Dip tip of eyedropper into warm lemonade mixture. Squeeze and let go of bulb to fill dropper. Hold filled eyedropper over shape in mold and gently squeeze bulb to fill shape to top with lemonade mixture. Repeat until all shapes are filled in both molds.
Place baking sheet with filled molds in refrigerator. Chill until lemonade mixture is firm, about 30 minutes.