The more often you tell children not to smoke or take drugs, the more you annoy them by wasting their time telling them off for doing something in the future which they have no wish to do. Do it too often and you actually push them into doing the very thing you're telling them not to do - they've been told off often enough already, so they might as well do the crime. Well, I'm not going to lecture them. Here's all I have to say on the matter:-
If you want to show everyone that you're a fool, take up smoking. You'll waste a lot of money on it, you'll stink, and you'll die early, but that's how evolution by natural selection works, so by all means take yourself out by smoking if you want to: it will only improve the species.
What about drugs? Well, they're actually for old people who are going to die soon anyway. Save them up until you're 80 and then if they kill you it won't matter because you'll already have had your life. I've never taken drugs because I don't want to damage my brain, but I certainly don't rule out the idea of taking them when I'm really old.
Alcohol is a different case - some alcohol is good for you, though not when you're a child. It destroys your liver and kidneys if you take too much, and it can give you throat cancer as well. Most alcoholic drinks also taste disgusting: people drink it mainly to forget their empty lives and to fool themselves into thinking they have friends - the alcohol makes them smile for no reason, and if they take a lot of it they think they love each other, but the reality is seen by the people who aren't drinkng: it's just a bunch of disgusting drunks drinking something that tastes like mud before throwing up all over the place and lying in a gutter. Only losers get drunk. The real trick to taking alcohol is to find drinks that actually taste nice and to have it in small quantities. Red wine with a meal can be nice, as can the odd glass of sherry in the evening or a tiny amount of single malt whisky (it's the taste that matters - after a few sips you can't taste it properly any more). But while you're a child, you simply aren't designed to take alcohol and anything more than a sip can damage you. I never drank any alcohol as a child and have no regrets about that. I would have liked the odd sip of it just to find out what it was like, but I now know that the things my parents were drinking tasted revolting anyway and I wasn't missing out. I still prefer ordinary fizzy drinks, but I do drink a small amount of alcoholic stuff for health reasons - you'll live longer if you drink some alcohol as an adult, but if you have too much it will shorten your life instead. As for the effect alcohol has on me, it just makes all the muscles in my arms sore. How does drinking small amounts of it make you live longer? Well, maybe it kills harmful bacteria inside you, along with killing healthy cells, but the balance might be beneficial if you don't drink too much of it.
So, why don't I need drink or drugs to make me artificially happy? Why don't children need them? Children already know how to live and how to have fun, though adults often try to stop them and lock them up in schools instead of letting them live. You must never forget how to be a child. You must never forget how to have fun. You should live your whole life like a child and spend as much time as possible playing. I refuse to grow up: I will not go over to the side of the enemy: children are the ones who have got it right and they don't need to be taught how to live, but most adults seem to want to destroy their fun and to drive them into a life of alcohol and drugs instead. Don't let them destroy you: the truth is that they actually don't care if you smoke, take drugs and drink lots of alcohol because it justifies the way they treat you: they think they have to lock you up in schools all day because you're too stupid to run your own lives sensibly, and every time they hear about a child smoking or taking drugs it makes them think they've got it right. But they haven't got it right: they have completely failed to provide you with the amount of freedom you deserve in accord with how well behaved and responsible you are. Children who smoke and take drugs are your enemy because you are made to pay for their stupidity, so there is no way any of you should ever imagine that they are cool.