Answer:
I think Paulsen wrote his story in such a way so we get a more objective point of view rather than drawing attention from the story with thoughts and hopes and whatnot. And since the backstory has already been explained, there is no need to have him filling in the story with flashbacks and whatnot, as some authors do. Since there are no other characters (depending on which of his books you are referring to) it is easier to write in the third person, rather than the first person where he would have given his thoughts and feelings on other characters, and interacted with them. A third person limited point of view combines many aspects of the first person and the third person objective, making this the most effective way to write his series.
Step-by-step explanation: