I had a quiz that contains 5 calculated questions. The quiz seemed to be working fine for the first day and a half. Then, at about 5:30 PM on the second day, the quiz suddenly stopped working. Students could get into the quiz and put in an answer, but when they hit Submit under an answer (correct I might add) it gets marked incorrect and a different data set is loaded. When I test it in preview mode the quiz worked fine, but when students tried it didn't work and still didn't work for the next 24 hours until the quiz was closed. The program also was marking questions wrong but giving student points somehow to the point where some students were receiving 25/10! I have never seen this error before and I have no idea how to replicate it again. I know that when different student kept trying it, it kept happening so it was not an abberition, but I have not had it happen on other quizzes. During the time the quiz was up, I did edit the question to include more unit choices in the question, but I didn't fundamentally change any of the question and I have edited questions during a quiz before. I have attached two screen shots that might help. I am willing to work to fix this, but I can't even guess what the problem is.