It is true that small amounts of pot has been legal in Alaska, but my concern is geared towards greater accessibility. Now that it is legal and will be sold commercially it will be much easier for young adults to attain. Usually the youth will steal from their guardians, just like alcohol.

I've been teaching 21 years and I can tell when a student has started smoking pot. When a young person begins smoking their grades usually drop and they do not seem to care. This may not be the case with adults, but it is VERY obvious when working with youth.

It's easy to believe there are situations you notice.

It's also easy to believe there are students where you don't notice.

I don't think increased accessibility is a legitimate concern. A pot smoking parent that can't keep their stash secure from their kids will be equally ineffective whether the pot was purchased from the black market or legally from the grocery store.

There will, however, be more pot smoking parents / grandparents / aunts and uncles / older siblings / etc.

While I agree that someone whose brain is not developed should not be using mind-altering anything, what you described is essentially puberty.

Heck, these kids shouldn't be drinking coffee or caffeinated soda, either.

I can clearly see the popular opinion (reddit/hacker news) is that marijuana is harmless. My professional opinion is different, however, and over the course of my career I have seen its affects first hand. Laugh and down vote me if you will, but the negative affects are real and damaging to youth and the research backs me up.

http://www.livescience.com/37889-marijuana-users-lack-motiva...

Without administering chemical tests to all of your students, you can't know with certainty which ones are using.

Sure, if a student has problems from it you will be able to observe that, but it's flawed reasoning to go from "I observe some students having problems" to "Using always leads to those problems".

And I don't naively believe that marijuana is harmless, but if you give me a choice between prohibition for everyone and (further support for) programs that reach out to students that exhibit sudden changes in behavior, it isn't very hard to decide.

My teenage relative's schoolmate went from being an excellent student and actress to a severe down-and-out in a short space of time due to her marijuana use. Likely other things contributed but the change was radical.