This contains excerpts from Richard's excellent observations (https://richardwindsor.com) in italic.
Well, first the spankings!
Here she is with Tab Hunter. I agree with Richard that this is very likely a promo pic for The Girl He Left Behind from 1956).
In Tab Hunter’s autobiography, and in interviews he has conducted since, he says that he actually did spank Natalie as the pics show for her 18th birthday.
Now the next pic IS from “The Burning Hills” and this time it is Nick Adams giving Natalie a spanking, one that she seems to be enjoying!! Again, after going through the pics available on IMDB, this is exactly the outfit she wore in the movie “The Burning Hills”. Now what is interesting though, while Nick Adams was in “Rebel Without A Cause” with Natalie, he WASN’T in “The Burning Hills”. We may never know why he was on the set of “The Burning Hills”, but it could be that the two of them had a friendship in part through James Dean, but also through Elvis who Natalie had dated and was also a very close friend of Nick Adams.
In the last spanking pic of Natalie I can’t honestly be sure that it is a spanking. It is from the 1962 movie “Gypsy”. One thing is for sure, the hand is definitely in motion!!
And here's the additonal bit of information that it is rather hot.
On July 29th, 1966, the actress, Jennifer Jones, hosted a party what was supposed to be known as “The Night Hollywood Embraced Esalen”, instead, it became known as “The Night Fritz Perls Spanked Natalie Wood”.
Natalie Wood was on the hot seat during an encounter group, playing her role with gusto. Fritz Perls attempted to get her to admit that she was acting but Natalie was too sly and skillfully slipped out of his verbal traps. Finally Fritz let her have it “You’re nothing but a spoiled little brat who always gets her own way” and he quickly hauled her over his lap and began spanking her. It was only a brief episode and after Natalie left it was Tuesday Weld’s turn on the hot seat, but there was no spanking this time.