why 4:20?

Factual Questions
1

4:20 (apparently the clock time) is associated with marijuana. Does anyone here know why?

2

I believe 420 is a police code for possession of marijuana, or maybe possession of any type of drug.

3

http://boards.straightdope.com/sdmb/showthread.php?threadid=79478

http://boards.straightdope.com/sdmb/showthread.php?threadid=67431

4

The term 4:20 is refering to a purchas of a 1/8th ounce of marijuana “for twenty” dollars.

5

I just felt the need to follow-up on my previous post in this thread and say that after reading the two other threads referenced by another poster, the police code explanation is apparently just a myth. I also did not see any conclusive answer to this question in either of the other threads, though I may have overlooked it.

6

I believe that it is the generally accepted time of day that school kids start to smoke grass as the result of being out of school and parents are probably not home.