Log into your Blackboard course and go the Control Panel:

1. Click on Grade Center.
2. Select Full Grade Center.

Locate the column that contains the student's assigment submission.  Hover your cursor over the cell that contains the student's submission, and click the chevron that appears in the student's cell.  Click on the option labeled View Grade Details.

You will now see the student's grade detail and a listing of the attempts the student made.  

1. To clear the student's attempt, locate the attempt you wish to clear and click the Clear Attempt button. You will then be presented with a dialog box confirming deletion of the attempt. Note: Clearing an attempt is permanent and all data associated with that attempt will be deleted.
2. To ignore an attempt and leave it ungraded, click the Ignore Attempt button.
3. To allow an additional attempt for the student, click on Allow Additional Attempt.  
4. When finished, click the button labeled Return to Grade Center.