So, I'd seen some gifs of the film from a few years before TOS in which William Shatner plays a schoolteacher while only slightly older than Kirk would have been when he was a teacher, and teaching similarly-aged students, at that. But I had heard literally nothing else about the film until I looked it up.
So, despite the absurdly sensationalist posters/taglines/etc, the actual premise of it according to Wikipedia is:
Peter Gifford is a teacher who wants to teach high school students to think for themselves and express themselves. A female student pushes to have open classroom discussion about the physical and emotional issues associated with teenage relationships and sex. This issue gets blown out of proportion by parents who don't have the facts and jump to ill-informed conclusions, demanding sanctions against the mostly innocent teacher, who keeps still on the matter to protect the involved students.
My first reaction was "huh, that sounds... both of its time and unfortunately still extremely relevant to ours."
Most comments I've seen about it are "pretty boring but if that was my teacher in 1961 I'd be thinking about sex too," which is funny but not terribly enlightening. However, the September 1961 reviews are kind of fascinating to read from the perspective of the future. Variety's:
This is a well-written, carefully considered and capably-filmed study of American youth which avoids the sensational aspects of Hollywood's similar pix. Canadian actor William Shatner doesn't have a large role as the teacher, but he registers sympathetically and effectively. He has a pleasant screen personality and brings a moving power of oratory...
You don't say.
