<p>There are numerous books, especially over the past 10 years, that discuss how the classes are selected. About 8 years ago, I started with Karabel, The Chosen, read the books in the bibliography and then read any books that quote it. That covered about 20 books. If you don’t have time, read the reviews on Amazon or another source. For Yale, Kingman Brewster’s 1965 letter sums it up pretty well. If you are applying there, it is very instructive.</p>