There are several fantastic classes by writers on MasterClass. A one-year subscription is $180 for all the classes you want to take.
Check out Neil Gaiman‘s class — quick preview below:
One of the most high-profile writing-related classes is by Shonda Rhimes, who’s behind Grey’s Anatomy, Private Practice, Scandal, How to Get Away with Murder and other shows. Not speculative fiction but her sense of pacing and drama is unparalleled and well worth learning from.
You can see a preview of her class here:
Other writers — and directors — who have classes on the platform include Dan Brown, David Sedaris, James Patterson, David Baldacci, Margaret Atwood, Judy Blume, R. L. Stine, Joyce Carol Oates, Jodie Foster, Spike Lee, Judd Apatow, Aaron Sorkin, David Mamet, Steve Martin, David Lynch, and Ron Howard.