I read Atlas Shrugged, as well as a few other Ayn Rand books (Anthem and Fountainhead) while I was in high school...I enjoyed them, but in the end I shrugged, since I had also been reading books by other writers who had philosophies more compatible with my own (I like to explore out of my comfort zone - it makes life more interesting).
It also helps to understand the psyche of many tea party and libertarian types who have adopted Ayn Rand as some sort of patron saint.
ADG