by David Sturrock.
Yes the activity completion options vary according to the type of activity module but file submission is definitely an option for an assignment.
in your model answer restrict access settings you define its visibility prior to the student having met its access condition. I suggest using the "show greyed out with restriction information" option so it is clear their file submission will release the model answer. You may also want to add some explanatory text in a label and/or within the assignment description. If you use auto linking when you refer to the model answer in assignment description, the student will be able to click the link to view the model answer as soon as they have submitted the file for marking.
