Thank you for your reply. Wouldn't it be possible and a lot easier to for instance incorporate something like a bookeo or comparable plugin?
If you're wanting a low cost method (I don't consider $39.95/mo Bookeo low) then use a Wordpress page for each course, Google calendar plugin for scheduling, and basic PayPal buttons for registration. Plenty of themes are available to make it look professional. If it's just a couple of people doing site administration this would be ideal.
[updated] There's a new plugin on Wordpress.org called Classdex that looks like it will do what you want. Since it is so new I would advise that you test it thoroughly first before deciding to base your business on it.