In 2000, Charles Best was a history teacher in a New York City public high school, spending his own money buying supplies for his students that the school couldn't provide. Then he had an idea.
"My students and I just wanted a way for teachers, like myself and my colleagues, to be able to tell the world about the books we wanted, and the art supplies," Best told CNBC's "On The Money" in an interview.
In one of the earliest examples of crowdfunding, he founded a website, called DonorsChoose.org. Public school teachers from across the country can post their classroom needs, and donors can fund any of those projects directly. Fast forward 15 years, and $334 million dollars has been raised from 1.7 million donors.
As CEO of DonorsChoose.org, Best says the site also lets people "support a classroom and see exactly where their dollars went." That money has helped nearly 15 million students and funded nearly 600,000 projects.
"About half the projects on our site request really basic materials. It could be copy paper and pencils, paint brushes," Best explained, while the other half are requests are for "field trips or butterfly cocoons for students to see the life cycle of a butterfly."
However, since the 2008 recession, Best says DonorsChoose has seen requests for more basic materials, "especially in low-income communities." The direct funding from individuals and corporate partners into public schools is filling a need that government education funding is not able to provide, he added.
"We see a lot of public schools, all over the country, where clearly whether the dollars are insufficient or the dollars are not reaching the classrooms," Best said. "There are students who go to school and do not have the books they need to develop a love of reading, or do not have the art supplies they need to love art."
Best said teachers at 63 percent of all the public schools have created classroom project requests on the DonorsChoose.org site. With the data that's available on the DonorsChoose website, there's a wealth of information. "People can actually see what resources are most needed, in particular cities and districts," he said.
The CEO said that data on the state of U.S. public education could help government officials make spending choices. "We think what policymakers and budget makers could do better is to listen to classroom teachers who we think know their kids better than anybody else in the system."
Last year, donors send $78.6 million dollars to schools through the site, up from $56.7 million in 2013.
Among this year's donors is Stephen Colbert. The comedian and television host is a member of the DonorsChoose board. In May, he announced he would donate $800,000 to fund all existing education project requests on the site from his home state of South Carolina.
Best called the request a "shock and awe of a philanthropic sort, and I cannot tell you what it was like for those South Carolina teachers when they saw all their classroom dreams being fulfilled."
—"On the Money" airs on CNBC Sundays at 7:30 p.m., or check listings for air times in local markets.