My experience traveling with teens made me realize you really need some planning from them. What you think are the great sights to see, they could care less. History, cultural significance, all that..nada. An example is the Anne Frank house. It means a lot to Americans in a certain age group, because we all read the book, maybe acted in the play, saw the movie, and WW2 was a tangible thing. Kids nowadays (yes, I sound old), it means little.
Have her do research, what are her interests? What does she want to see? You can help her discover interesting things, but you really can not plan it for her. You also have to figure out that your pace may not match hers. Our daughter, after a bit, was fine spending the afternoon in the hotel room texting friends and watching TV. (After a week into a 3-4 week trip she insisted we let her fly home, we vetoed that)
I think it comes down to you winnowing things down to one or two things a day that she "must" see, then one or two things she found, then some down time here and there.