Pam,
     I've never taught film, but I had a course in intro to film in
  undergrad and Kawin's  How Movies Work was informative.  It does not deal
  only with American cinema, but it situates Western film in a collective
  historical context.  Because of its thoroughness in teaching-the-basics,
  it is possible to build a course around it, be it historical or political.
     I have a good bit of film resources in the form of articles, but I can't
  recommend anything until I know more about your objectives.