Facebook FB +0.93% cofounder and CEO isn’t only interested in spreading Internet access overseas. Mark Zuckerberg said on Thursday that he and his wife Priscilla Chan are donating $20 million to a nonprofit, called Education Super Highway, that helps make strong Internet connections available in U.S. classrooms. The couple’s donation underscores Zuckerberg’s intent to spread Internet access globally, a goal he is pursuing through Facebook’s Internet.org project, as well as the couple’s commitment to digital education tools. The couple gave $3 million to the same nonprofit in 2013. In a Facebook post, the 31-year-old billionaire said the donation should ultimately expand access to personalized learning, in which education is designed to help students learn at their own pace through customized approaches. Improving the speed and reliability of schools’ Internet connections will make it easier for students and teachers to take advantage of personalized education software and online tools, Zuckerberg said. The executive noted that while most U.S. schools have Internet, less than half have high-speed broadband. “Every classroom should have fast internet access, and thanks to EducationSuperHighway, President Obama‘s ConnectED initiative and the work of many other partners, we’re making great progress,” Zuckerberg said. “One day we’ll connect the world and provide personalized learning for all students, and we’ll keep focusing on this until that happens.” ConnectED is a project President Obama started in 2013 that aims to ensure that 99% of U.S. students have access to broadband Internet by 2018. Zuckerberg and Chan have been seriously involved with education philanthropy for years. In 2010, the couple donated $100 million to public schools in Newark, New Jersey. In 2014, they pledged an additional $120 million to San Francisco-area schools. This year, Facebook started a project with Summit Public Schools in the Bay Area to help build personalized learning tools, which could be used around the country. The couple also recently founded a prekindergarten and elementary school that caters to low-income families near Facebook FB +0.98% Menlo Park offices. The school does not charge tuition and offers health care and other services for families. The school is expected to begin accepting students next summer.