let me tell you a true story. A while ago I got really drunk, I was probably .3. I threw up a TON. But I LEARNED from my mistakes. Now I know to drink responsibly. do you think it's better to learn now, or when I'm 21 at some college party, when if I got alcohol poisoning everyone would be too drunk or high to care or know what happened?
Which would you rather your children do?
Back on topic, a 15 year old, even if you don't think is fully an adult, is not a child. If you think a 15 year old is the same as an 8, 9, or 10 year old, you sir, are a complete and utter dumbass.