Not really. There are kids like that out there, rising above the stereotypical middle-schooler crap, I guess the only unbelievable thing to me is how they're all pretty great people in different ways, all of them, and they're all a group. I guess they're not to begin with, so that makes it less unbelievable. Not out of the question though.
I also think, me-being-an-a-hole aside, that there's been a bit of a dumbing-down of the culture in the last 10 years or so. Kids are simultaneously MORE grown-up now in terms of the information they have access to, and LESS grown up at the same time.
Sure, some of the smartass one-liners from Marco and stuff might be a little too witty and biting, coming from an 8th grader or whatever, but not by much. Some middle-schoolers are dumb shallow brats, others aren't, all I'm sayin'.
Ads for the "adjusting to new circumstances" bit, the younger the better for that. Yay for science!