I think Kipling's "Just So" stories have similar references.

An interesting example of this is the evolution of the opening chorus of the musical "Showboat".

This is a chorus of black workers singing:- "N*****s all work on the Mississippi." Apparently the N word was used by the black workers in a sort of tongue in cheek reference to themselves, and Oscar Hammerstein's lyrics were intendedin a satirical vein, much of the musical being laden with social comment.

The lines were changed to:- "Darkies work on the Mississippi" then "Coloured Folks work on the Mississippi" then "We all work on the Mississippi", and finally no-one worked on the Mississippi as the opening chorus was left out.

It does however, put a teacher in a difficult position, particularly with a junior class, when such "loaded by context" words appear in a class reader. I think I would just tend to avoid the text.