As the $100 million he donated to the Newark, N.J., schools makes its way into the district there, Facebook founder and CEO Mark Zuckerberg announced Tuesday he will donate $500 million of his company’s stock to education and health causes.

The Silicon Valley Community Foundation, an organization that manages philanthropic donations, received 18 million shares of Facebook stock for a valuation of just under $500 million (though that valuation has varied quite a bit during the company’s up-and-down IPO). Zuckerberg made the announcement, naturally, on his personal Facebook page, without providing specifics on what the money would go toward beyond “education and health.” Those two areas are the major priorities of another technology tycoon, Bill Gates, through the Bill & Melinda Gates Foundation. Both men, along with their wives, have signed “The Giving Pledge,” a promise to donate “the majority of their wealth” to philanthropic causes.

Recently, another signee, Star Wars creator and LucasFilms Ltd. owner George Lucas, announced he would donate much of the $4 billion generated from the sale of his film company to education-related causes. Wealthy business leaders have long been attracted to education philanthropy as a way to fund the country’s future and, in turn, generate a better workforce (or, as some say, to influence education policy; but that’s a story for another day). But a recent wave of philanthropists such as Gates have been more targeted with their donations, focusing on returns on investment.

Zuckerberg’s contribution to Newark is managed by a local nonprofit, the Foundation for Newark’s Future. The money is only unlocked if matching private funds are raised, and there are specific focus areas where the money can be spent. The donation has created new schools and teacher programs but sparked concern that it is part of an effort to privatize the district (as Zuckerberg himself notes, 11 of the 15 new schools created are charter schools). Most notably, Zuckerberg’s donation will pay for the merit bonus system that is part of Newark’s new teachers’ contract. It will be interesting to see if there are similar stipulations for this larger donation and whether it is targeted toward specific geographic locations.

Zuckerberg’s full announcement:

Two years ago, [my wife] Priscilla and I signed The Giving Pledge, committing to donate the majority of the money we earn to charity.

Our first major project has been around education reform with Startup: Education in Newark, NJ. I’m really proud of the work we’ve done there, helping leaders like Governor Chris Christie and Mayor Cory Booker sign the most progressive teachers contract in our country, opening four new district high schools, 11 new charter schools and more.

Today, in order to lay the foundation for new projects, we’ve made a contribution of 18 million Facebook shares to the Silicon Valley Community Foundation. Together, we will look for areas in education and health to focus on next. I’m hopeful we’ll be able to have as positive an impact in our next set of projects.

The Gates Foundation helps support certain areas of coverage by Education Week.