Polling some catholics at my office today, I was astonished to hear them say, "Immaculate Conception? That's about the conception of Jesus, right?"
Huh!! At least my kids knew (because I had been drilling them), and my mother knew (old pre-Vatican II that she is), but my husband - ah, CCD kid that he was - failed at the quiz.
Holy Blessed Virgin, Mother of God, who was conceived without sin, pray for us!