Matt Cimber - He & She (1970)

Matt Cimber's "He & She" (1970) was another film with a fake "sex research institute" - and was noted as the first hard-core porn film to get national distribution. In the film, an attractive young couple demonstrated the art of lovemaking while a sex education professional narrated.

Africanus Sexualis AKA Black Is Beautiful (1970) - Matt Cimber

IMDB review:

Black Is Beautiful is one of the lucrative explicit-sex films marketed alongside Scandinavian imports during a brief window when Supreme Court decisions (notably the Quiet Days in Clichy and I Am Curious (Yellow) cases) first opened the floodgates that now have led to hardcore porn's dominant place in our culture. Cimber cashed in while the getting was good with a series of fake documentaries now classified as "white-coaters", which within 2 years were driven out of the marketplace by porn films with a storyline. (Ironically, today's internet-dominated XXX market has generally jettisoned story lines, coming back full circle to 1970-level content.)