Apparently Zuckerberg will be setting up a company that will house $100 million worth of Facebook shares for his pledged donation to the New Jersey schools. Andrew Ross Sorkin for the New York Times writes:
People involved in the donation process say that the Facebook shares pledged will be worth $100 million based on the company’s own internal valuation, not the value assigned by the secondary market.
Sounds like a sweet deal for Zuckerberg, he may only have to give up one single share.