Story I heard was similar to what CB said but a little different.

A group of kids would all smoke pot after school at 4:20pm by a statue at/near their school and eventually it caught on to the mainstream public, as to how it applies to the actual date (April 20th) your guess is as good as mine.
GreenGiant07 Reviewed by GreenGiant07 on . 420 ?? Hey everyone iv bein smokin strong for the last 6 years and i still dont understand how 420 is such a big day and a big number in the stoner world i celebrate 420 every year but i still dont understand the signifigance of the sumber 420...anyone know? Rating: 5