When the author attempts to gain the audience’s personal trust, the author is using ethos.
Sunny~ ☺
Well if its a "real word" may depend on dialect, or where your from specifically. There are many words in Texas not really recognized as "real words" like "y'all" or many things like that. Perhaps it is a word somewhere. But I have never heard it. Remember, language is like a liquid, always shifting, and changing.
The significance of Ernesto Galarza's memoir taking place in California in the story is that the story tells of a Mexican boy beginning school without knowing the language or culture of the place.
The boy was an immigrant who has not inkling of what he will face as he begins his life journey in California.