Mary Cooch

Are you the only admin on your Moodle? Are you root admin? Do you have ftp access to your Moodle?

Tiffany - I am not sure you can delete a scale that is being used in assignments.

This is the way it should work - they should only  have on their list of courses the courses they are enrolled in. If they are seeing all courses then go to site administration>users>permissions>assign system roles and check they have not been put in as student there - that makes them students everywhere. Take them out and assign them individually in their courses or let them enrol themselves. If your students are not assigned in system roles then check your default user is "authenticated user" and not student.

Hello there - yes you have definitely been hacked. This is a good starting point if you read this: http://docs.moodle.org/en/Hacked_site_recovery

"I have it set up so that admin can assign roles" - if you mean the role of Moodle Admin, they should be able to do it automatically. YOu assign the role of teacher/student in a course by going to the course admin block of a course and clicking on assign roles there -what happens when you try to do this?