Every year, the National Film Preservation Board selects 25 films to preserve for the National Film Registry. The NFPB accepts nominations from the general public for up to 50 films, due by Aug 15. These are my selections; would love to see lists from others.
From NFPB : "The Registry is intended to reflect American society and the rich tapestry of American cinema since its inception around 1890. To that end, we strongly encourage the nomination of the full-range of American film-making: not just Hollywood classics or other well-known works, but also silent era titles, documentaries, avant-garde, educational and industrial films, as well as films representing the vibrant unmatched diversity of American culture, both in terms of content and all those who created these snapshots of America society: directors, writers, actors and actresses, cinematographers, and other crafts."
To nominate: https://www.loc.gov/programs/national-film-preservation-board/film-registry/