Hong Kong (CNN) -- China's extraordinary climb to the world's second largest economy was built on the back of Chinese workers, many of whom left rural farms to migrate for work in coastal factories.

But as China's wealth rises, workers are demanding a greater share of the wealth and better access to social services. And as this month's edition of "On China" examines, the young generation of worker are tech savvy, aware of their rights and choosier about where they go for work.

"They're on the Internet more ... on especially Weibo, China's social media, Twitter-like thing. They're able to connect with others, see what others are doing," William Nee of China Labor Bulletin, a Hong Kong-based NGO which defends workers' rights, told CNN.

"And in cases where there are strikes or things like that, they can put it out there on Weibo and other people can learn about it," he said. "They can look online for labor rights and labor contract law."
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One of the greatest issues for China's 250 million migrant workers is the "hukou" system of household registration. Migrant workers often can't register in the cities where they work, and subsequently can't qualify for social services such as public education or social security.

"When I talk to migrant workers about a vast array of problems, I think, this usually rises to number one," Rob Schmitz, a Marketplace correspondent in Shanghai, told CNN. "And I think, for them, the biggest reason this is such a big problem is that they are treated like illegal immigrants inside of their own country."

This hits the children of migrant workers. "Many children are born in these larger cities where their parents have moved to. This is their hometown, as far as they know it," Schmitz