I handle a lot of cases involving college students who smoke marihuana everyday. They sell it in order to supply themselves with weed. I also see it with men and women in their late 20′s and early 30′s who are now in the work force. The youngest age for starting marihuana for my clients was age 11. I had one today tell me she started at age 9. It leaves you speechless, because she is talking about elementary school.