Preheat the oven to 350 degrees. Spray a 9x13 baking dish with cooking spray.
Mix together the flours, sugar, oats, brown sugar, baking powder, and salt. Use a pastry cutter to cut the butter into the oat mixture until it resembles coarse crumbs.
Sprinkle half of the mixture into the pan and pack tightly. Spoon dollops of the strawberry preserves around the crust and spread evenly with a knife. Sprinkle the remaining oat mixture over the top and pat down lightly.
Bake 35-40 minutes until golden brown on the top.
Cool completely in the pan before slicing into squares.