My feelings of how fun all of this was aside, the experience was enlightening.
The conclusions to be drawn from this are simple; consumerism is a bigger part of most kids' lives than nationalism. Not to say that nationalism isn't huge--the kids have certainly bought into the "<3 China" campaign launched since the earthquake in Sichuan, and have a great deal of pride in China, but so do other countries, certainly, like the US. But in their daily lives, among friends, pop culture has a greater hold (again, like the US). These wealthy urban kids--China's future--are happily swimming in China's new consumer culture; they enjoy spending, dressing up, going out. They also keep telling me they think that China's relationship with the US is extremely important and valuable, and polls of these kids agree wholeheartedly.
So ultimately, I am beginning to believe that, despite rather rampant nationalism, these kids aren't going to become the foundation of an angry, aggressive China. They'll be the foundation of a more tame, money-obsessed one. And as far as foreign policy goes, that's great.