What you have here is an opportunity that few people will ever have. Yes, you have worked hard. But you have also been blessed with the God-given talent that separates you from all the other hard workers who did not make it here. The decisions you make while you are here will have consequences that will shape the direction of the rest of your life. You can look back and remember this as the greatest time of your life -- or as the setting for your greatest disappointment and regret.
The gift you have been blessed with is so special that you will attract others to you without even trying. They will want to be close to you, anxiously trying to somehow be a part of it. You will be celebrated by people you don't even know -- and who may not always have your best interests at heart. Guard your gift jealously. Be particular about who you get close to. "Friends" who may tempt you to stray from your path will likely have far less to lose than you.
You could be forgiven for getting caught-up in the adulation. There will be times when you feel the temptation to forfeit your own good judgment. You owe it to yourself to remember what is at stake and why you are here.
...or words to that effect.
But honestly, they probably already hear some variation of this many, many times. Kids don't listen. Even the ones that somehow manage to stay out of trouble are probably more lucky than good.