Hi Yury,
From what I've seen on the English and Arabic Wikipedias, a course page is created for a specific class for a specific time period (semester/term). For example, you might have a History 101 class in the Fall 2014 semester, and a History 101 class for the Spring 2015 semester. Each of these would have a separate course page, even if it was the same curriculum and the same instructor -- mainly because the list of students and articles will be different for each term.
The course page helps organize classes, but can also serve as a historical record of the course and help with cohort analysis with tools like Wikimetrics. So again, it's best to keep the student list there and start a new course page for each term or editing period.
You may also notice that the term is automatically included in the course URL structure on wiki in parentheses (). For example:
Hope that helps!
Tighe