In a blender, combine raspberries and 1/3 cup sugar and blend until smooth, scraping down sides as necessary. Pour through a fine-mesh sieve into a 2-cup measuring cup, pressing lightly on solids (you should have about 2/3 cup puree); discard solids. Whisk in 2 tablespoons yogurt.
In a clean blender, combine cantaloupe and 1/3 cup sugar; blend until smooth. Pour through a fine-mesh sieve into another measuring cup, pressing lightly on solids (you should have about 3/4 cup puree); discard solids. Whisk in 6 tablespoons yogurt. Fill six 3-ounce ice-pop molds halfway with raspberry mixture, then top with cantaloupe mixture, slowing pouring down sides of molds. Insert ice-pop sticks and freeze until solid, 2 1/2 to 3 hours (or up to 1 week).
To remove ice pops, briefly run the molds under warm water, then gently pull sticks until pops release.