Sift flour, sugar, baking powder, and salt together into medium mixing bowl.
Melt 2 1/2 Tbsp margarine in frying pan until melted; Be sure to tip the pan side to side to coat/grease all over.
Pour melted margarine in a small bowl, add water and egg (if you want to add egg); Mix well.
Mix blueberries with dry ingredients, just before adding the liquids.
Stir liquid mixture into the dry ingredients until it is thoroughly moistened; It is OK if this batter is lumpy.
Cook the pancakes over medium-high heat on the stove-top (or 375F on electric frying pans); Cook pancakes until the tops are bubbly and the bottoms browned; Turn the pancakes over to cook other side (Approxiamtely four minutes per side).
Serve hot with margarine, honey, brown sugar or maple syrup.
Actual cooking time will depend on the size of the pan you are using; I have a small frying pan, so I have to do these individually; My mom has a griddle large enough to cook them all at once.