In an unnamed American college town in the mid-1960s, four students and a young English teaching assistant (who narrates) circle like moths around the flame of a fifth, the impossibly beautiful and serene Allison Kern. Their stories are told in flashbacks while Allison lies in a coma in hospital, having fallen from a cliff in a bizarre accident while camping with the others.
Their young lives, otherwise spent aimlessly and pleasantly in a haze of marijuana and acid, are brought to a crisis by the unfolding Vietnam war and the threat of the draft, which brings them into conflict with authority. Finally, looking back on events from the Bicentennial year of 1976, the teaching assistant, now established with a career and family, ponders the strangeness of those times.
I'd compare it with Updike's novels of that period, perhaps Rabbit Redux in particular; also with Philip Roth's Indignation, which similarly deals with the draft and its paralyzing effect on potential draftees.