This is always a concern for a parent. How do approach and help without pushing them away and causing them to use even more. One way that I have seen may work is that you don't come in making rules saying that they need to stop or else. Try to say that you are there to help, you want to understand why they are smoking and what you can do together.
Very carefully. Your son is going to assume that you are trying to "attack" him and will probably become very confrontational.
I am not 100% sure on how this will work, but maybe if you approach him and let him know that you know about his marijuana use, you do not approve of it, and when he is ready to talk about it you will be there.
Your son has to make the decision to stop, you cannot do that for him so remember that. The more you forbid the behavior, the more he will want to do it more. Good luck!
Tell him you are here for him and concerned about him using it, but you aren't going to attack him or punish him for it. Try talking to him about the effects marijuana has on a person. It causes memmory loss, makes you unmotivaded and lazy, makes you temperarily stop caring about things. Also how expensive the drug is and how people who rely on it blow all there money. I wish my parents handled it differently with me but they used the attack and demand method which only made me want to use it even more like the other guy said.
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