I don't know why this is being upmodded. These kids are NOT wasting their energy. In China you can't drop out and move to the valley and start a company with your computer savvy.
The system in China is simple: To even have a CHANCE of successful, professional, middle class (by Chinese standards) life, you MUST get a university degree. To get a university degree, you MUST score in the top Nth percentile of the college entrance exam.
Students get sent to top schools because top schools produce results on this exam, as absurd as the actual exam may be. You have to consider that despite the fact that for the country as a whole these things may not be ideal, for any individual student you would be stupid not to put everything you can towards that test.
And if you don't get a degree, you end up as a laborer of some sort. And in China these people work their asses off and are poorer than a homeless jobless American. It's a different world.
The country has so many people there is far more competition for jobs and resources, and because of the government the current rules are the only way up through the system. Obviously there is a problem with the system, but it should be abundantly clear that it would not be in your best interests to rebel against it before getting through it--you would only hurt yourself turning down the best schools and the entrance exam, and you would not be in any position to effect any changes.