As Timothy says, you can make the Journal module visible by accessing the Modules section in the Configuration panel (you need admin access rights).
The reason that it is invisible is because it has been superseded by the improved 'Assignment' module (not the exercise module). Within the improved Assignment module you have a choice of 3 assignment types:
- Offline activity
- Online Text
- Upload a single file
This assignment type asks users to edit a text, using the normal editing tools. Teachers can grade them online, and even add inline comments or changes.
(If you are familiar with older versions of Moodle, this Assignment type does the same thing as the old Journal module used to do.)
(If you are familiar with older versions of Moodle, this Assignment type does the same thing as the old Journal module used to do.)
When I upgraded from 1.4.4 to 1.5.2, all of my Journals were automatically converted to this new Assignment module. I think you'll find this new version much better than the old Journal module.

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