They do tend to think that they're going to live forever, but their fearlessness teaches them boundaries too.
My adolescent nephews took to leaping out of a first floor bedroom window onto their trampoline in the garden whilst the grown ups were away.

Boing. Another broken arm but hey, my sister's so used to turning up at A&E with one of her three sons in tow that the staff there greet her like an old friend.
Bet that pissed her off mightily. How much was this to do with the fact that had she died the parents/guardians may have been liable? They were covering their own back, so to speak.
You see, this is where I have to disagree. We think that there will be exploitation becuase culturally we've become much more prudish about sex between people of wildly different ages. If we look back in history this was not the case. Why do we now consider what would once upon a time been considered an instructive and nurturing relationship between an older mentor and a younger person to now be 'exploitation'?
Ok, I'm going to throw something really rad into the conversation now, because I was thinking about this the other night after reading this thread.
Imagine if it was socially acceptable (the social norm) for an older person to 'take on' a teenager once they reach the age of consent,
if the teenager wanted a sexual mentor for the first few years of their sexually active life? The mentor's role would be to show them how to make love like an adult and get max enjoyment from one's sexuality, and maybe verse them in other aspects of the adult world.
It wouldn't preclude the youngster from having a regular teen boyfriend or girlfriend as well. The older mentor would be approved by the parents/guardians of the teenager so that they knew they trusted them to care for their son/daughter.
What harm would come about if society was more accepting of sex between teenagers and older men and women and there was a social acceptance of such relationships, as I describe above?
Discuss!