Some statistics about Bible knowledge in American society:

Only half of adults interviewed nationwide could name any of the four Gospels of the New Testament. Just 37% of those interviewed could name all four Gospels.

Only 42% of adults were able to name as many as five of the Ten Commandments correctly.

Seven in ten (70%) were able to name the town where Jesus was born, but just 42% could identify him as the person who delivered the Sermon on the Mount.

38% of Americans believe the entire Bible was written several decades after Jesus' death and resurrection (While this is true of the New Testament, the entire Old Testament was written hundreds of years before the birth of Jesus Christ).

My personal favorite:
12% of adults believe that Noah's wife was Joan of Arc.

49% believe that the Bible teaches that money is the root of all evil. (The love of money is said to be the root of all types of evil).

75% believe that the Bible teaches that God helps those who help themselves.

(Thanks JongMin.)