In glass measuring cup or small bowl, stir together 1/2 cup of the yogurt and the chocolate syrup. Spoon mixture into ice pop molds, dividing it evenly to fill each mold about 1/3 full. Freeze for 30 to 45 minutes until set. Divide 2/3 cup yogurt evenly among the molds on top of the chocolate layer. Insert sticks. Freeze for 30 to 45 minutes until set. Purée strawberries in food processor until smooth. With a wooden spoon push mixture through a fine mesh strainer into a bowl, extracting as much juice as possible. Discard solids. Whisk in sugar and 2 T. of the yogurt until well mixed. Spoon mixture evenly among the molds on top of the yogurt layer. Freeze until firm, at least 4 hours or up to 1 week. To unmold pops, run hot water over outsides of molds for a few seconds, then gently pull sticks. Makes 6 pops.