We have developed several custom applications to teach a variety of computer science topics. These tools integrate with Canvas via LTI, and we have automated the process of adding this content to Canvas. In particular, one tool will show the student text material and visualizations associated with topic, as well as embedded mastery questions that are presented to the student via an assignment of type “External Tool”. The student’s attempts to answer these questions are passed back to the gradebook via the LTI interface.
What we have discovered (which was new to us but probably not to you), is that if you use the “Until” date in an “External Tool” assignment to limit student attempts after a certain date, Canvas will not display ANY of the content from an external tool. It just shows the student a message that the assignment is no longer available. This makes it impossible to limit the time students can answer the questions, and also see the material when using an external tool to source the material. It’s an either-or design issue. We can’t think of any reason that for the “External Tool” assignments, Canvas shouldn’t continue to show the content, and then check to see if the “until” date has passed, and if so, just ignore the grade passback.
If you set the “until” date on a standard Canvas assignment, it continues to show the content (that which is entered in the RCE), but disables submission.
We think that correct behavior is for :
1) Canvas to continue to show the external tool content when the "until date" has passed, adding a message at the top saying the submission date has passed.
2) Canvas should add a check to the gradebook where new grades passed back form an LTI can be ignored after the "until date" has passed.