My senior year of high school, I took an elective unit of American lit, which was taught by a teacher who was really burned out and had no business still being in a classroom. After a couple of weeks of wrangling the class lunkheads, who were only interested in screwing around, one day she simply passed out a stack of "find-a-word" puzzles and stopped teaching entirely. For the rest of the term I spent my time either in the library or actually reading the textbook, which is where I first encountered "Walden." It was love at first read. I have a copy of "The Annotated Walden" that I got in the late '70s/early '80s, which was immensely helpful in understanding some of the more obscure references.
Come to think of it, I need to re-read Walden. And probably Emerson's essays, too. They were both books that moved the 17-year-old me beyond description.