In a screw-top pint jar, combine 1/2 cup whole milk, 3 tablespoons sweetened condensed milk, and 2 teaspoons matcha powder and screw on the lid securely. Vigorously shake the jar until the contents are uniformly combined. Take the glasses from the freezer and pour haf of the matcha milk into each glass. Top each glass with carbonated water. Swirl with a large spoon and enjoy immediately.