Most likely it is because you have students that have already attempted the assignment. You will need to delete all of the attempts by selecting them and choosing to delete them if you need to add/remove questions from an assignment.
If you are developing a new assignment where the attempts have just been trials then deleting the previous attempts will have no consequences in the grade book.
If this is not the case think carefully about how to handle the graded attempts.
There are several ways of getting to the attempts # which you need to click on to delete the previous attempts. Use whichever works for you.
Click on the assignment that you want to amend. It will take you to a page with attempts # at the top.
If you are on a page with the message “You cannot add or remove questions because the assignment has been attempted (attempts #)” Click on "attempts #".
If you have navigated away from the page with the message go to the Settings block > Assignment Administration > Edit Assignment.
Whichever way you find attempts #, click on it and you will go to a page with a drop down menu at the top.
- Select all users who have attempted the assignment.
- There are several other click boxes, select whatever applies to your situation.
- Click Show Report and then select all.
- Click Delete selected attempts and confirm selection.
- Go back to Assignment Administration > Edit Assignment and you will now be able to add or delete question