Rebecca Riccio tried to keep her expectations low.

Yes, the first massive open online course — or MOOC –on philanthropy that she’s teaching had the backing of billionaire¬†Warren Buffett¬†and his sister, Doris.

But it was a four-week, no-college-credit course offered during the height of summer, mid-July through mid-August. Absolutely the worst time to try to draw a crowd for hitting the proverbial books.

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“I would have been happy if we got 1,000 students,” said Riccio, founding program director of Northeastern University’s Students4Giving program, in an interview. “Instead, we got 10,000 students, from 70 countries and all over the U.S., including California.”

Doris Buffett has pledged to give away more than $100,000 over time to the course through her Learning by Giving Foundation.