An education nonprofit in San Rafael has received a $42 million donation from philanthropist MacKenzie Scott, the former wife of billionaire Amazon founder Jeff Bezos.

The donation to 10,000 Degrees is the largest gift in its 45-year history, said Kim Mazzuca, the president and chief executive officer.

“We are deeply grateful for Ms. Scott’s confidence and investment in our mission and proven college success model,” Mazzuca said. “This extraordinary gift is not only a bold affirmation of the power of education, but it is a vital investment in our communities at a time when it’s needed most.”

The organization announced the donation this week, but Mazzuca said she learned of it in a surprise phone call on Sept. 10. She kept it confidential, sharing it only with the nonprofit’s board.

“Ms. Scott’s gift will have a profound and lasting impact — significantly increasing our support for our students from their first step toward college through graduation and into meaningful careers,” said Guy Lampard, chair of the board. “With this support, our students can build generational stability for themselves, their families and their communities, forever.”

Scott made no public statements about why she chose 10,000 Degrees, Mazzuca said. However, Mazzuca said she knows that Scott’s organization “has been vetting us for some time,” focusing on student outcomes.

The nonprofit supports 12,000 high school students and 4,300 college students from eight counties by providing peer support, financial aid management, workshops, small group education and scholarships.

This past year, the nonprofit gave $10 million in scholarships to college students and helped them leverage the money to an additional $73 million in free financial aid. The aid to college students also includes an assigned paid peer mentor to help each student navigate issues on campus such as housing, academic support, transportation and health care.

The high school student support is administered on the school campuses, Mazzuca said. The students are guided to attend community colleges for two years, and then transfer to a four-year college for the last two years.

Community colleges are not only more affordable, but 10,000 Degrees students have been shown to have better success by starting at a community college and then transferring, Mazzuca said.

The new grant is “absolutely going to allow us to expand our reach in existing communities and even in some new communities,” she said.

“It is really going to allow us to catapult to a much greater impact,” she said.

The nonprofit provides support to 300 high schools in the region, Mazzuca said. In addition to Marin, the other counties are Napa, Lake, Sonoma, Contra Costa, San Mateo, San Francisco and Santa Clara.

“Marin County is our longest-standing market, even leading San Francisco and Sonoma,” Mazzuca said. “We are in all Marin high school districts.”

All students who receive support from 10,000 Degrees are from low-income families. About 92% of students are the first generation in their families to go to college, and about 92% come from communities of color, Mazzuca said.

Mazzuca said a portion of the grant will go toward hiring new staff so the nonprofit can expand its reach. Another portion will go to increasing scholarships.

Mazzuca also hopes to use some of the grant money to explore artificial intelligence programs that help with college success.

The mission of 10,000 Degrees is “to achieve educational equity and to support students from low-income backgrounds to and through college to realize their full potential and positively impact their communities and the world,” Mazzuca said.

Since its founding in 1981, the nonprofit has supported more than 80,000 students and delivered more than $113 million in scholarships, she said. She said 80% of its four-year college students graduate, double the national average. Its community college transfers also graduate from four-year colleges at twice the national rate, she said.

Scott has a net worth of about $34 billion, according to Forbes. She received the bulk of her fortune after divorcing Bezos.

In 2019, Scott signed the Giving Pledge, an initiative encouraging wealthy people to give much of their fortunes to charity. The campaign was started by Bill Gates, Melinda French Gates and Warren Buffett.

Scott promised to donate more than half her wealth. So far, she has given away about $19.2 billion. Last month, she donated $70 million to UNCF, the United Negro College Fund.

The Associated Press contributed to this report.