Hi, Sandy. I agree, this episode came out so much better than I thought it would. I really felt bad for pretty much everyone involved except the two cheerleader types.
Sam just wanting to be normal.
Dean trying to pretend he doesn't care about anything.
Barry getting beat up and harassed until he couldn't take it anymore. I'm glad it wasn't his spirit hurting people.
Dirk taking out his anger on everyone around him because he didn't have anyone to turn to.

I didn't think Sam exorcised the ghost, I thought the salt drove him out.

I loved Sam's "what I did last summer" paper about killing werewolves, esp. 'cause I read a fanfic about Sam handing in a paper like that.

And I too thought that Dean would hate the teacher if he knew who gave Sam the idea to leave. Though if it hadn't been him, it would have been someone else. Sam was/is too intelligent not to stand out, even if they are only there for a few weeks.