"lest"

In eighth grade American History & Social Studies class in Clifton, New Jersey, I once used the word "lest" in answering a test question.

When I got back the scored test, the word was circled, and points had been deducted.

So, I asked why. Had I used the word incorrectly or improperly?

No, I was told, the problem was that "no one really uses that word."

From this we can conclude that we should not assume that all teachers aim to inspire all students to achieve their best, lest we forget that the educational system provides a warm home to conformity and anti-intellectualism.