Old people suck, but they've been through it all and know more than you. Kids today are just like they were when I was a kid, they think they know everything. My oldest daughter is 10, and she is constantly trying to tell us what's up. I don't know what it is about kids thinking they are so smart; because ultimately, they are very dumb.
Now Gwennie (my oldest) is VERY book smart. She leads her class in academia and does better then dad did, even though I'm a freaky genius. Common sense, on the other hand, has seemed to elude her. My wife and I do everything we can to help that out, but it seems as though she is at war with the common good.
Example: We asked her to clean the kids bathroom one day and she grumbled, but we expected that, then she reluctantly rose and went to work on it. She did just as she should, she worked her way from the top to the bottom like anyone with sense would do... but that's as far as the sense carried. She then showed us her progress before she started to sweep and mop, and it was pristine. "Looking good," we told her "now finish it up please." I happened back by the bathroom about 3 minutes later and saw that she had taken dirty floormats and the garbage can and placed them upon the clean surfaces, inevitably dirtying what she just cleaned. Now anyone with common sense would've thought, "Better not put these on the nice, clean surfaces." but not Gwennie. So then upon attemting to explain to her how that wasn't the best way to go about it, and that she should've moved the things OUT of the bathroom, she turned to us and attempted to educate us on the situation beginning with her favorite word, "actually."
That word is enough of a sentence for the wife and I to stifle her every time. We are thoughtful in the way we run our household, and in the way we teach things to our kids. We've never steered them wrong in any way, and (hopefully) never will; and yet, somehow Gwennie believes she already knows everything. I used to think it was just her being a brat, but after some recolection and consideration, I realized that in general, kids typically don't respect their elders. I can't explain why this is, but I have a theory.
When I was her age I didn't dare talk back because I would feel it in the morning. Children don't fear their parents anymore, nor any other adult figures. I say bring back the fear to instill the respect. I'm not saying to beat your kids, but as long as they think it's possible that you could at any given moment, I bet they'll spend a lot less time acting up and a lot more time doing EXACTLY what you want them to do.
Ultimately, kids are great, they are a treasure to be treasured... but man do I want to beat them sometimes.