What I'm sort of shocked by in this thread is how many people believe that age 18 (or college) is when they should START to give their kids some freedom and start to teach them to be an adult. In my opinion, that should start much earlier, with 18 being the end goal. You may not think of your child as an adult at 18, but society does and that can have severe consequences -- legally (by now facing real consequences if they break the law) and financially (by being able to enter into legal contracts and get into financial trouble). I think you are doing a disservice to your children by not preparing them for that.
I totally agree. I live in a community where we have an epidemic of helicopter parents many of whom have seemed to redefine successful parenting as getting your child into an Ivy League university. The overwhelming majority of kids in my town will go away to college where they will be able to do virtually anything they want to any time they want to. Their parents know this, or at least they should know it, and yet there is very little effort to teach them to be self-sufficient individuals capable of navigating the world in an adult manner. I've got four years before my oldest goes away to college, and when that day comes, she needs to be able to make sound decisions for herself without me and her father next to every step of the way. She could be at a college thousands of miles from our home - I won't be able to come to her rescue at the drop of a hat.
On our family's trip to WDW in April, I'm planning on letting our two oldest kids (14 and 12) have some free time in the parks without us. They will have cell phones and times when they are expected to check in with us. If we go back in a couple of years, I will expand this to going to a park without us on Disney transportation. Since two years after that she could be off who knows where doing who knows what, I need to make sure she is learning how to be responsible while she is still living with with me a majority of the time.