I have used a workaround to copy a quiz I make in Canvas in order to modify the quiz for special needs students. I make my original quiz, send it to commons, then pull it back to the same course. Once I have this copy, I edit the name, change the questions and end up with two versions of the same test. Recently, two other teachers and I have noticed that after students take the modified test, if we want to allow them a second attempt, it strangely reverts back to the original test. How and why is this happening? It has happened to all of us.
I’m not super familiar with copying from Commons, but I’m pretty sure Eric is correct and that’s why people do not use this as a way to make multiple copies of their quizzes.
I’m pretty sure the best way to do this right now (until the new quizzing engine comes out) is to copy the quiz back into your course. So in the course with the quiz go to settings, click on import content, select the course you are in (it will warn you with a red triangle), make sure to select import specific content (NOT all content). Then when you get the option to select content check the box only for the specific quiz or quizzes you want to copy. Once you do this it will create a copy of your quiz. At that time make sure to rename it! You can then go back in and make another copy of the quiz as needed. I’ve tested this and was able to make at least 8-9 copies.