My oldest already has smoked weed, her mother flipped out when she found out (which is ironic as hell).
When her mother told me I just replied with,"so what's the problem here, you smoke it too so why make a case out of it"?
My daughter and I had a simple discussion about it andwhat she thought of it. She said she actually had tried it a couple times and decided it wasn't something she liked, since that time she hasn't done it. She also knows my stance on it being that it is no different than booze, but if she gets caught for it then she is responsible for her actions so be smart about it and who you get it from if you decide to do it. My youngest was also present for this conversation.

I hide nothing from my kids, if they ask they get the answer whether they want it or not.

 

I think i'd be somewhere similar to this. My oldest is only 4 though and a lot can change in a decade (I was 14 was when I first smoked if i recall correctly).