This is the time to teach them choice, response to society preasure, and responsiblity.
Teach them how to make the right choices for themselves.
Teach them to be strong enough to say no to peer preasure SHOULD they want to.
Teach them about responsible fun.
I know my ex is a huge pot head. Can't function with or without. Doesn't pay support. At 35, he has to take a bus to pick up his kids on weekends and takes them to his mom's house where he doesn't pay rent. He has nothing there for them. They have to bring toothbrush, clothes, etc from home because he can't supply them, but he has enough to by about 70grams of weed a week. That is about $280/month.
I know my father is a huge pot head. Worked everyday for 45 years of his life so far and is still at it. Single father of 2 kids 15 years ago. Ya when fathers really had no rights. Has no debt, pays his taxes, votes, pays all his bills. Put a roof over our heads, food in our belly and loved us with all his heart. My dad smokes at least a 1/2 oz a week. Probably about $600/month on pot.
Both above are pot-heads, one is responsible enough to handle it, the other is not. That is the difference between responisble fun and addiction.
Teach that to your kid.