This isn't a prayer request, but I had a prayer request before for my 2 final exams this past semester. I read that the prayer to St. Joseph of Cupertino is very powerful for all those taking any exams. I prayed his prayer many times a day and right before the test.
The prayer really works and helped me to do well on the exams.
So for anyone taking exams, pray to St. Joseph of Cupertino and you will do well!!