Survivors of World War III, Matt and Dani meet a wise old man who gives them advice about the survival skills they'll need in the deadly ruins of America.
I read this series when I was young. Post apocalyptic teenage kids surviving in a post nuclear holocaust, trying to cross the country on foot. I kept watching for subsequent books after #4, but they never materialized. I finally went scrounging around the internet today to see what it was called and see if there were more than 4. Alas, the saga never concluded. Ah, nostalgia.