To add additional time to a student's exam, you can use the Reset option:

• Go to the Manage Exams screen 
• Find exam - click into the Responses column
  • 
• Find the student's name - click into the Reset column
  • 
• Update the fields as appropriate - click Save
  • 
  • Submitted = No
  • Reset Method = Extend Exam
  • Extend Original end time by: 8 (or whatever amount of time)
  • Submit Count = 0 

If needed, you can also manage a student's specific access time. This can be done by going to the Manage Exams screen and clicking into the Access column.