One of the Boys. It's such an underrated album. Thinking of You, I Kissed A Girl, Waking Up In Vegas, Hot n Cold, I'm Still Breathing and If You Can Afford Me are all amazing tracks which trounce all of TD's songs.
I've never been able to finish a single one, but One Of The Boys because its singles are better than the crap she's been releasing since Teenage Dream.
Thinking of You alone >> all of Teenage Dream & Prism.