I teach high school math and like to use short answer questions for my exams. I create large question banks where the exams take random questions to create the test. This discourages cheating. Grading these exams is a nightmare. I have to complete each problem as I grade because that is actually faster than trying to find that particular problem on a printed answer key.
I would LOVE to have the ability to attach the answer to the problem as I create it in the question banks. This way when I go to grade the question I can see their response and my correct answer right away.
For example: When testing on systems of equations, I don't want to use multiple choice because the students will substitute in the values to find the correct answer. I want them to solve the system and type in their answer. Currently, I have to solve each system when it's time to grade or look over my enormous answer key to try to find the problem that they were given. If this feature were added, I would be able to see their problem, their work, and the answer all on the same screen.