Did you know that the origin of the number 420 being associated with pot comes from a story by H.P. Lovecraft? In Within The Walls of Eryx, he wrote:
"My route must have been far from straight, for it seemed hours before I was free of the mirage-plant's pervasive influence... When I did get wholly clear I looked at my watch and was astonished to find that the time was only 4:20".
It's true. Check Wikipedia.
P.S. The picture to the right comes from here. It teaches kids how to grow your own pot. Remember to ask an adult for help!