Details about Poe's time at West Point are somewhat scant (a good overview is provided by Karl Oelke). We know that he took part in an encampment at Camp Eaton, that he paid for dance instruction, and that there was a masquerade ball that summer (if Poe attended is unclear). From camp, Poe moved into the barracks on August 30; his roommates included Thomas W. Gibson of Indiana and Timothy Pickering Jones of Tennessee. Classes began on September 1; Poe enrolled in French and mathematics. Only a few days into the semester, Poe's "Sonnet — To Science" appeared in the Saturday Evening Post.
During this time, Poe's foster-father John Allan's illegitimate twins were born to Mrs. Elizabeth Wills. He was courting Louisa Gabriella Patterson of Elizabethtown, New Jersey at the time. Patterson became the second Mrs. Allan on October 5, while Poe was still at West Point (allegedly, Allan told her about his illegitimate children before the wedding). The wedding was held in New York, not far from West Point, though Allan did not bother visiting his foster-son. Poe wrote of his disappointment and assured Allan he had "a very excellent standing in my class... the study requisite is incessant, and the discipline exceedingly rigid." He also notes he has seen General Winfield Scott.
Poe apparently did very well at West Point, all while continuing his writing (usually focusing on humorous comments on military life or his officers). One fellow cadet named David Emerson Hale wrote to his mother, the influential editor Sarah Josepha Hale, that Poe "is thought a fellow of talent here."
Nevertheless, Poe was not suited for West Point life. He also was upset at his foster-father's sudden remarriage and increasing disinterest. By January, he had given up and expressed himself rather forcefully in a letter to Allan. "Did I, when an infant, solicit your charity and protection, or was it of your own free will, that you volunteered your services in my behalf? ... Under such circumstances, can it be said that I have no right to expect any thing at your hands?" Poe singled out the abrupt end of his "liberal education" at the University of Virginia, which Allan was responsible for ending — and, ultimately, Poe blamed Allan for his current situation, stuck and unhappy at West Point. He had asked Allan to help him secure his dismissal but Allan remained silent in his mansion. Poe vowed, "From the time of my writing this I shall neglect my studies and duties at the institution." Allan did not respond (other than a personal note where he wrote, "I do not think the Boy has one good quality."), and Poe made good on his threat.
Poe was eventually tried for Gross Neglect of Duty and other charges. His court-martial, held on January 28, 1831, resulted in his dismissal from West Point, finally ending Poe's ill-fated attempts at a military career.
*The image above depicts "The Plain" at West Point in 1828.