Defining Science Fiction
Kansas University’s Gunn Center for the Study of Science Fiction has this useful overview of the defining traits of science fiction. We will use these in class discussions.
http://www.sfcenter.ku.edu/SF-Defined.htm
Of course, playing into genres are reader expectations, so we may as well cover typical character types. Jason Hellerman has a useful infographic on these:
https://nofilmschool.com/12-character-archetypes-for-your-screenplay
The key here, though, is that we do not merely point out the existence of such types. Good writing (a loaded term, of course) defies and plays with our expectations.