In a medium saucepan, combine the sugar and cornstarch

Add the water, and cook until boiling

Boil for about a minute or until the mixture thickens a bit

Add the blueberries

Pour into a 1&1/2 qt. casserole dish

Put little dots of butter around the blueberries, and sprinkle with cinnamon

In a small bowl, combine the flour, sugar, baking powder, salt, and shortening

Use a fork to mix everything together until the dough is divided into coarse crumbles

Add milk, and stir until doughy

Spoon the dough onto the top of the blueberries in several places

Bake at 400 degrees for about 30 minutes

Best if served warm

Optional toppings - whipped cream, or vanilla ice cream