I don't have any kids, but I would read the story as is and explain what the different words/meaning are and why we don't use them anymore. Not only would they learn about the past, they won't get confused/mocked in school when they try to talk about the edited version of the story.
____________________________Shaowstrike (Retired - FFXI)
91PUP/BLM 86SMN/BST 76DRK
Cooking/Fishing 100 "We don't just borrow words; on occasion, English has pursued other languages down alleyways to beat them unconscious and rifle their pockets for new vocabulary."
— James D. Nicoll