I remember my parents, and their friends, having the book when I was a kid. And that movie was a two-part TV one that everyone watched. This would've probably been about 1976 or so (pre-Star Wars, post-Jaws...I use favorite movies as time-markers to remember things because I know where I was living, what grade I was in, etc. from all that. I know I'd seen Jaws already (1975), but my life had yet to be permanently altered by the other (1977).
When I was little, I thought it was a horror movie (in some ways, it probably is), just from the book cover and the tone of the promos for the TV movie. I didn't know, back then, what the story was about. I didn't full appreciate Ms. Field until a year later, when she was barefoot in a Trans-Am for two hours.