The urban legend experts at Snopes.com note that several theories are worth considering. Some believe that the day falls on April 1 because of the arrival of spring, when “nature ‘fools’ mankind with fickle weather.” Another possibility: The holiday “is thought to commemorate the fruitless mission of the rook (the European crow), who was sent out in search of land from Noah’s flood-encircled ark.”
Regardless of the origin, people show no signs of giving up the tradition. The number of Web searches for “april fools day prank ideas” are scary high. Everyone (and especially parents) should be on the lookout. That “$1,000 cell phone bill” your daughter hands you might not be the real McCoy.