Sorry to resurrect an old thread, but I'm another one that can't fathom even asking the question about a 17 year old. Did you never send your kids to summer day camp?
I grew up less than an hour from Disney, and went to day camp every summer. We went on field trips regularly to all the area attractions, and the rules were simple: under age 7, must be with a counselor. Over age 7, just don't miss the bus at the end of the day. Sure, the counselors were in the same park, but this was before cell phones, they were barely over 18 themselves...we weren't exactly "chaperoned." The age 7 rule was to conform with theme park regulations...kids of that age are even free to go Halloween Horror Nights by themselves
If their parents allow it, of course.
By 16, I was living in my own apartment in downtown Orlando, driving my own car and working at Universal. It would have been rather odd for my parents to not allow me to visit the parks unaccompanied, don't you think?
Some parents have different thoughts though. I had a friend FROM day camp whose mother obviously wasn't aware of how things were done there. We were 10 or 11 when the mother dropped us off for an afternoon movie, telling us she would be at least an hour late picking us up. The theater was in a pretty rough area, and was one of those dollar places that only opens up for specific showtimes, so no way to wait inside. However, there was a nice seafood restaurant next door.
After the movie, I decided it would be safer/better for us to have some lunch while we waited. I always saved my allowance, so I had plenty of cash. I treated my friend to a fairly pricey table service meal (left a good tip too). We exited the restaurant about five minutes before the mother was due...she'd gotten there five minutes before we came out.
She was furious!! She couldn't fathom that I would have been so irresponsible as to take her daughter to lunch instead of waiting in the parking lot (where someone had been kidnapped and raped a week prior). I got yelled at all the way home, and she later called my parents. Boy was she mad when my parents took my side!
So the point is, sometimes kids actually have more information than you do, and often can be trusted to make mature, responsible decisions. I think it's a matter of teaching your kids the skills they need, and then watching them to see when they actually start to utilize those skills. At that point, they can be trusted in that situation. JMO
.... aslong as they meet us later casue it is a family vacation after all 
