The passage is called "the professor is a dropout"

in paragraph 2, johnson writes that “[lupe's] school records state that she is
ret_rded ” but in the next sentence, she writes, “how did lupe quintanilla;
"ret_rded nonlearner, become dr. quintanilla, respected educator? why does
johnson put the word “ret_rded” in quotation marks in the second sentence;
but not in the first? what is she implying? can you find another place where
johnson makes similar use of quotation marks?