Before we can begin assembly, we need to cut some notches in each side of the shelves. While the notches will be 3/8" wide, the length of the notches will depend on the method used to create the dadoes. The purpose of the notches is to allow the shelves to seat properly all the way to the bottom of the dadoes.
For instance, if you used a stacked dado set on a radial arm saw to create the dadoes, you'll likely need a longer notch than if you used a router. If you used the stacked dado set, your notch may be as much as 1-1/4" long, as opposed to the notch necessary if the dadoes were created with a router will be as little as 3/8".
To cut the notches, use a fence on your band saw to set the 3/8" width and cut a notch in the each of the sides of the shelves, cutting from the front with length as noted above.