[dainbramaged]

Apparently, 420 refers to 4:20
Yes, time to light up a joint after school. Most of the dopes don't realize it's also Adolf Hitler's birthday - maybe they never heard of him.

[FourtySeven]

Apparently, 420 refers to 4:20 Yes, time to light up a joint after school.

That may be true now, but back in my day, when I used to walk to school uphill both ways, the term "420" was taken from the supposed ideal time to plant marijuana seeds, for optimal growth and harvest in the fall. (4/20, or April 20th)

I don't think it's any small coincidence that April 20th is also "Earth Day".