Mr. P is Junior’s math teacher. He becomes part of the novel in chapter four and five, specially in chapter five “Hope Against Hope” where Mr. P talks to Junior and convinces him to change school for the reason that Junior is special and very smart.
At the end of chapter four the character “Mr. P” is described as “a weird looking dude” (p.38 l.25). There is also a cartoon on page 39 where the reader gets a more detailed image of Mr. P’s physical appearance. He is drawn very thin and small but with a very big head in contrast which is similar to Junior’s appearance. A funny thing about Mr. P is that he sometimes “forgets to come to school” (p.38 ll.27-28) and because of that he “sometimes teaches class in his pijamas” (p.39 l.4). So I would interpret the character as a forgetfull and awkward person but his mistakes make him likeable. This is also why the pupils like him; he doesn’t expect much. Relating to the conversation between Junior and Mr. P in chapter 5, the reader learns that Mr. P has still a bad conscience because of his past, when he helped to try to kill Indian culture. The fact that he visits Junior at home while being suspended from school lets me conclude that Mr. P is a teacher who really cares and worries about his pupils. He is a sympathetic and helpfull person.
The Absolutely True Diary of a Part-Time Indian by Sherman Alexie 