Quiz

I'm working on porting a public speaking class into Moodle. There are worksheets that are being ported as well.

As far as I can tell, the Quiz Module is the best way to incorporate these into Moodle. And essay seems to be the best quiz types for almost all of these questions.

But these worksheets have questions like: What is the purpose of a conclusion? We'd like to have some sort of a grading guideline for questions like this, but I don't see anywhere to place this where it will only appear for the grader and not for the student.

Any ideas?