Why do I see the resource and activity drop-down lists in Moodle?
If you see two drop-down boxes when you turn editing on in Moodle (as seen below)
Your activity chooser is turned on. You can change this by clicking on the Activity Chooser On link in your Setting menu (left column).
Clicking on this link should restore your editing view to see one link in each week/topic box for Adding an Activity or Resource.