How do I "upublish" them as a group so they don't show up when I publish the course? I will be publishing a few each week over the semester.
Currently, I do not believe that is a feature in Canvas - well, not an easy way to do it.
However, if you use this as a workaround (Adjust All Assignment Dates on One Page ) then you can change the publication status and/or dates as you see fit all on one page.
Someone else in the community posted the following idea that you might want to vote up and/or contribute your use story to:
Retrieving data ...