This was a very short story that was read to me when I was a child in the early 80s.
The story was one of many in a collection in one book. My mother seems to think it came from Reader’s Digest.
I believe there are 2 or 3 black boys who are trying to cross a river in Africa when a crocodile came up through the water at one on them. The water was muddy so he couldn’t see it coming. The crocodile grabbed his leg then his arm. The croc had him in a death roll. I forget how he got out of it, but the boy survived to tell the tale.
This story had me on the edge of my bed when my mother read it to me.