As a parent and a concerned adult in the lives of many kids, I have learned a couple of things. First, I find that being honest is the best policy. I remember being a teenager; I made poor decisions and did things I knew better than doing; I have never pretended to have been a perfect teenager because kids see through that crap in about half a second, and it teaches them nothing except to lie and hide things from you. Second, when kids do things they are not supposed to do and make decisions we know are bad, it usually has nothing at all to do with the parents or their parenting skills - the majority of parents do their best to do right by their children - and the majority of teenagers are only thinking about themselves and what they want when they are driving the adults around them crazy and worrying them to death - that's just basic adolescent psychology.
I guess my point is this, be honest with the kids in your life and with yourself as well. Don't pretend you were a saint and don't fool yourself into believing the kids are saints. Adolescence is difficult enough without subjecting children to a perfect ideal that the adults in their lives believe they should hold themselves to, or worse yet putting them in a situation where in their still-developing brains, lying to the adults who care about them seems better than letting them down.”