Character Analysis
You should probably do ahead and refer to Piper as Miss Bossy-Pants because this chick definitely wears the pants in the Alcatraz friend group, leading Moose and the other kids on mischievous missions. She's kind of the antagonist in our story, even though everyone ends up friends at the end of the day.
Much as Piper's a, shall we say, natural leader, we're thinking part of her appeal—at least with Moose—has to do with her looks. Look at what happens when he first sees her:
My face turns red just seeing her. She's a looker.
[…]
The girl has freckles and full lips like a movie star. (3.42-45)
Piper isn't just easy on the eyes, though. A wallflower she is most definitely not—this girl likes to be the center of attention: "Piper still waits like she's not going to open her mouth until she has every single person's eyes on her." (7.23). In other words, Piper's a bossy beauty, and she likes it this way.
It only makes sense that somebody with looks to kill and a huge desire for attention has to do some work to stay at the top, though. And how does Piper do that? By putting other people down. As Moose puts it, when she wants his help with a project: "'Why should I help you? You treat me like something stuck to the bottom of your shoe'" (12.30). Oops—looks like that whole treat-people-like-dirt thing doesn't always work out in Piper's favor.
Piper might not agree with our assessment, though, because arguably, she has bigger fish to fry than some pesky peers. This power hungry kid prefers accolades from the most powerful person she knows: her dad, a.k.a. the warden on Alcatraz. To this end, she's good at covering her tracks, readily setting her friends up to take the blame for her own bad ideas (remember the laundry service scheme, for instance). And even when she does get in trouble, Piper keeps up her cool, calm, and collected appearances, "saving face" (38.46) by saying her punishment is actually fun.
What is Piper's mission in life? She wants to meet Al Capone. But despite her scheming brain, she just can't make any progress. Even though she doesn't meet her personal goal, though, she has the connection needed to help Moose reach his. When Moose writes his letter to Capone, Piper slips it into the mail that her mom has censored, finally using her fondness for rule-bending to help someone else out.
Which brings us to a happy ending: Piper and Moose end up being friends. When Natalie's in trouble, Piper is able to put aside her high-and-mighty ways to help: "I've never known Piper to take orders from anybody before, but she is now. We are a team and Nat is in charge" (34.1). Aw. Looks like as much as Piper likes to break rules and run the show, at the end of the day, what she really wants is to feel needed.
Piper's Timeline