Preheat oven to 400°; grease a 13x9-inch pan.
Combine flour and baking soda; set aside.
In a medium bowl using a mixer, cream butter and sugar until light and fluffy. Stir in the flour mixture until well blended. Beat in the oats with a wooden spoon; dough should be crumbly.
Press half of the dough into the pan. Spread jam over it. Crumble the remaining dough over the jam and pat lightly to cover. Bake 20-25 minutes.
While still warm, cut into bars and remove from pan. Cut them as large or as small as you like, but I warn you: they're addictive!