Preheat oven to 375 degrees.

Sift together flour, baking powder, and salt.

Stir in the oatmeal and sugar.

Cut butter in with a pastry blender, until the mixture forms small crumbs.

Pat 2/3 of the mixture into the bottom of a 9 x 13 inch pan.

Spread preserves on top of crust (warm preserves, if necessary, to make them easier to spread).

Sprinkle remaining crumbs over the preserves.

Bake about 35 minutes. Cut the bars when the pan is still warm, but wait for them to thoroughly cool before removing from the pan.