When I was in, what would be the equivalent of the eighth grade, one of the teachers gave my class a life lesson on drugs and drugs use. Of which I am sure would get him in a lot of trouble, had he talk of this in USA.
He told us that if we wants to try drugs, it is better to wait until we are adults. Because then we will not interfere with the physical development and be responsible enough to take care of ourselves. He also said that he tried a bit if almost everything from marijuana to meths. And then he give warnings not to never ever try heroin because it will hook you from the first time.
I find that this is a sound advice. I have never tried drugs and never have the urge to do so. The closet thing I ever tried is popper :P For some reason, it never give me the affect people were raving about... Just a sniff of something that smell strange.