I was disappointed to discover a few years ago that the “Attendance” register in Brightspace does not connect to grades so I made up my own solution which works well.
If you require attendance in your class, here’s how I manage attendance in my class.
Step 1. In Grades, I create a scheme called “Weekly Attendance” that looks like this: 
Step 2. Create a item for each date you want to record attendance AND apply the Weekly Attendance scheme to the item:
Step 3 : Enter grades for that item and you should have a drop down box that looks like this:

