For the green layer, combine 2 cups grapes, 1/2 cup kale, and 1 tablespoon sugar in a blender. Blend on high until smooth. Pour mixture through a fine mesh sieve, pressing down on the solids to squeeze out all the juice. Taste and whisk in more sugar a teaspoon at a time until it is sweet enough for your tastes.
Pour 2 tablespoons of the green juice into each mold (a small funnel makes this much easier).
Place in the freezer and freeze until solid, about 4 hours.
Combine 1/2 cup lime juice, 1/2 cup water, and 3 tabelspoons of the sugar. Whisk until sugar is dissolved. Taste and add more if it is too tart.
Pour 2 tablespoons of juice into each mold, insert popsicle sticks and freeze until solid.
Blend the 1 pound strawberries and remaining 1 tablespoon of sugar in a blender utnil smooth. Strain mixture through a fine mesh sieve like you did with the green layer. Taste and add more sugar if needed.
Pour 2 tablespoons of the strawberry mixture into each mold and freeze until solid.
To remove from the molds, run the paletas under warm water until they slide out of the mold. Paletas will keep in the freezer for up to a week.