A lot of kids think the point of drinking is getting drunk.  But if you're a parent, it's important to show your kids that simply isn't the case and that you can drink responsibly.  The effects of alcohol on teenagers and adults is different though... which is probably the cause of the many misinterpretations.  Alcohol has less of an affect on teen's motor skills and coordination, which probably helps them to think it's okay to drive while drinking.  Because certain regions of their brains aren't fully mature, normal teenagers are inherently more suseptible to the thrill of risk taking, have stronger emotions, and are more heavily influenced by friends and adults.  When you add alcohol to the mix, all of these tendancies are exaggerated.  Also, while alcohol has a sedative affect on adults, it doesn't appear to have that affect on teens, meaning they stay awake longer and consume more. 
The safest thing is to protect the developing brain from alcohol.  I always felt like I would've turned out different if I hadn't started drinking.  There's no denying that teenage brains can't handle the affects of alcohol, that's why the drinking age is 21, not 16.  The parts of the brain that govern judgement, insight, decision making, emotional control, planning, reasoning, learning and memory-- the last to develop, are being transformed for adulthood... it doesn't make sense to go through all of these stages drunk...  you'll miss out on making decisions about college, careers, dealing with demands at school and work, getting behind the wheel for the first time, and seeking social and romantic relationships with peers as never before.