Add the TA to the class as a student and then change his/her status to Grader:

1. Log in to USFconnect and click on the Blackboard tab
2. Select the course you whish to work with
3. Enroll the student (or earlier, ask him/her to self-enroll)
4. Click on Control Panel at left part of screen
5. Click on List/Modify User in the User Management section
6. Click on List All tab
7. Click List All button
8. Select Properties for the student at right part of screen
9. Scroll down to Role and Availability section (4)
7. Click button next to Teaching Assistant under Role
8. Click Submit