Place the sugar and water in a saucepan. Bring water to a boil. While water heats to a boil, stir sugar to dissolve. Remove sugar water from the heat and cool to room temperature.
Red Popsicle Layer
Place the sugar water, watermelon, and red food coloring (if using) in a blender; blend until smooth. Fill the bottom 1/3 portions of popsicle molds with the watermelon mixture. Place the molds in the freezer for 1 ½ hours or until the watermelon mixture has hardened. When hardened, remove the popsicle molds from the freezer.
White Popsicle Layer
Place the sugar water, coconut milk, and coconut extract (if using) in a measuring cup; stir. Pour the coconut mixture into the popsicle molds (over the hardened watermelon mixture) until the molds are filled 2/3 full. Insert popsicle sticks into the molds and place molds in the freezer for 2 hours or until the white second layer has hardened. When the coconut mixture has hardened, remove the popsicle molds from the freezer.
Blue Popsicle Layer
Place the sugar water, raspberry extract, and blue food coloring in a measuring cup; stir. Pour the blue mixture into the popsicle molds until the molds are full. Place the molds in the freezer until hardened or overnight. Enjoy!
Note: When freezing the popsicle layers, make sure that each layer hardens completely before adding the next, otherwise the colors might run together. When pouring the liquids into the popsicle molds it will be less messy if you can use a cup or vessel with a spout.