Dunno, Steve - Peter Yarrow wrote it (along with somebody else). He says it's a kids' song, and didn't have anything to do with marijuana. That's been what Peter, Paul & Mary have said all along about the song - although they have occasionally made fun of those who have made or believed the marijuana allegations. Noel Paul Stookey staged a court trial of Puff in one of his monologues. The matter has come up time and time again over the years, and Yarrow has never said anything that would be considered an admission that it's a marijuana song. What his private thoughts were when writing the song are anybody's guess.
If you look at the whole song, it seems to be a song about the loss of the innocence of youth. Jackie Paper grows up and doesn't play with toys any more. If it were a song about marijuana, I think there would be more references to, more than just what some people pull out of the chorus.
Click here for a previous discussion.
Click here for a more detailed discussion of this issue, plus a particularly insipid MIDI of the song. Or, Click here.
I've also found others on the Web who firmly believe it's a song that was meant to persuade kids to smoke marijuana - but their documentation is pretty weak.
-Joe Offer-