1. Combine sugar and water in a small saucepan; bring to a boil, stirring constantly. Boil 30 seconds, remove from heat, and let cool 5–10 minutes.
2. Mix lemon juice and yogurt in a large bowl; add sugar syrup, and stir until smooth. Add blueberries. Spoon into a 15-count ice-cube tray (silicone works best), and add pop sticks; freeze about 3 hours or until firm.