Michael was already enrolled in Dartmouth,but dropped out to enlist. After his return,he planned to re-enroll in Dartmouth without telling his family,but Fate stepped in.
The novel says: "When Michael Corleone was discharged early in 1945 to recover from a disabling wound, he had no idea that his father had obtained his release. He stayed home for a few weeks, then, without consulting anyone, entered Dartmouth College in Hanover, New Hampshire, and so left his father's house. To return for the wedding of his sister and show his own future wife to them, the washed-out rag of an American girl." I take that to mean that Michael had no connection with Dartmouth or Kay before the war.
