The Exeter School's
http://library.exeter.edu/dept/Special/separate_peace/index.html
own page on author John Knowles, who was a student there, and on his novel A Separate Peace. Includes several articles about the book, Knowles' own comments on the novel, and information about Knowles' other works.
Brief essay on the rites of passage in A Separate Peace.
Brief but somewhat helpful summary and list of issues in the novel.
Information for a course on adolescent friendships in literature, and focusing on A Separate Peace.
http://www.yale.edu/ynhti/curriculum/units/1980/1/80.01.03.x.html
Some interesting character insights and plot discussions.