It makes the headlines when Facebook founder Mark Zuckerberg donates $100 million to help improve New York Public schools. Or when Bill Gates and Warren Buffet pledge most of their vast fortunes to charitable purposes.

But not in the headlines but just as meaningful is the charitable giving of ordinary people, many of whom seem to be making great personal sacrifices to help others financially.

“We’ve got over 120 stories of people all across the economic spectrum who are making big gifts,” says Jason Franklin, professor of philanthropy at New York University and executive director of Bolder Giving, a nonprofit that supports and spotlights everyday philanthropists.

“There’s a spark of passion around the potential for big giving,” says Mr. Franklin. But, he says, those who do not have the deep pockets of billionaires are extraordinarily generous.

“If you look at averages across the country, actually working class people give a higher percentage of their income than the wealthy do,” he says. “They give three to four percent versus the one to two percent that the wealthy give.”

“When we look back in 50 years, I hope this year will mark the start of a decade of outrageous generosity and a shifting American culture of giving,” says Mr. Franklin. “You don’t have to be a billionaire to be giving boldly.”

It’s reported Thursday that Mr. Zuckerberg is also joining the Giving Pledge effort along with 16 other billionaires, including Steve Case, a co-founder of AOL. Larry Ellison, who founded software giant Oracle Corp., and film director George Lucas.