IIRC, the quote for the novel “1984” goes something like this:
“Newspeak is the only language in the world whose vocabulary gets smaller every year.”
http://en.wikipedia.org/wiki/Newspeak
BTW, I am vehemently opposed to altering the text in any standard edition of the author’s work. However, if it will encourage the reading of the novel by children who would otherwise not have it available, I think replacing the “N word” with slave in a special school edition (and in school editions only) is fine. Fine just as long as the reasoning for the changes in the text are clearly explained to the student reader both in class and in the text and all instances of the change are appropriately identified (italicized, footnoted, etc.).
Perverting Nigger Jim's name in a school edition only is, IMO, the worst of all options. School is for learning, not for hiding from the truth.
The graduates of these special schools are going to complain about casting when they see a film about Spartacus leading a slave revolt against Rome.