Below, you'll see any text that was highlighted with comments from the reviewer.
I'm getting a hipster vibe, mainly from the combo of the beanie and the coupon for a gelato, along with the type of music that's currently playing on the ipod. Then there's the old classic: The Wind in the Willows. Megan probably fancies herself an adult (especially since she has a coupon for a gelato, not just straight up ice cream). Yet I get the rebellious streak with the crumpled up note from the teacher. Adding that to the family photo, her family life probably isn't picturesque at the moment but she still loves them regardless. I'm guessing she under went some personality change since she stopped bothering to talk to her penpal.
Honestly, I don't think one in particular tells me more than the others. They all come together to create a very three dimensional view of your character Megan: teenager, fun hipster, still into the classics, loves her family but gets into trouble, changed since she last talked to her penpal, and likes gelatos. Each item adds a vital piece of information to the character you've created.
I love how you got really specific. Sure, you didn't give me the name of the penpal or where he/she is from, but that isn't really necessary to Megan's character. So not only were you specific, but you were specific in the details that mattered. I really liked your piece. How well did my inferences match what you pictured each item to represent?