To create a structured course page, you'll need the course instructor right for your Wikipedia account. (If you go to Special:Institutions and see the option to "Add a new institution", then your account already has the necessary rights.)
You should now request the instructor right by posting on the education noticeboard. Describe your course and what your students will be doing on Wikipedia. Wikipedians may offer feedback on your assignment plan, and you may be asked to revise it if your plan goes against best practices for Wikipedia assignments. (It may be somewhere between a few minutes and a few days before your request gets processed. If you're anxious to get started, try leaving a message for one of the education program Regional Ambassadors.)
After you've posted your course instructor right request, return here to continue.