Pre heat oven to 425 degrees
1. In a saucepan, combine sugar and cornstarch, stir in water. Bring to a boil; stirring constantly, boil for 1 minute. Add blueberries. Pour blueberry mixture into a lightly buttered 1 1/2-quart baking dish or 9-inch pie plate. Sprinkle with cinnamon and drizzle with 1 teaspoon melted butter.
2. Sift together the flour, baking powder, and salt. Pour milk and 3 tablespoons melted butter into a measuring cup; add to flour mixture all at once. Stir just until mixture is moistened and forms a ball. Drop spoonfuls onto the blueberries. Bake for 25 to 30 minutes, or until lightly browned.