Did you know that there are one million earthworms in an acre of soil, or that an average American eats 10 pounds of marshmallows in a year? Did you know that the act of yawning and stretching at the same time is known as pandiculation? These facts, and hundreds more in a wide variety of subjects including history, science, sports, music and more, make Hmm...I Did Not Know That a must read for trivia buffs and fact fanatics.