I'm just seeing that some new update to the LMS has made "Gradebook" a pop out window with a new format. This new format completely dropped the option to add an assignment from this tab. I have always added assignments directly from the gradebook - I like to see the numbering system for previous assignments, etc - and find this much more convenient. I don't want to click back and forth between Assignments and Gradebook. Waste of time.
This is added to the new gradebook as of this morning! Apologies for the confusion -- in the interest of getting out the overall changes as far in advance of the school year as possible, there are a few additional pieces of functionality being added in over the coming weeks. Check out this video at the 4 minute mark for an overview: https://www.youtube.com/watch?v=trXxu7uTodM&ab_channel=BlackbaudSupport