I don't recall being assigned anything by Wiesel in my Iowa high school in the late 70s, and I took all the highest-level literature courses available. On the other hand, we sometimes were given choices of what to read, and it's possible "Night" was on book lists and that I simply chose other books.

Certainly by the mid 80s I was well aware of Wiesel by reputation, but I didn't actually read any of his books until 1990, and then I read most or all of them in something like a binge.