Khan Academy: Model for future of U.S. education?

World's most popular teacher doesn't show his face in online tutorials so students focus on the work, says Khan Academy's Sal Khan. Watch "60 Minutes" on Sunday, March 11 at 7 p.m. ET/PT

(CBS News) He teaches millions of students a month, yet none of them has seen his face. Sal Khan is a disembodied voice on the Internet, but his teaching method has become so effective that he may be the future of American education. Dr. Sanjay Gupta speaks to Khan and to educators who use his popular educational website, "Khan Academy," for a 60 Minutes report to be broadcast Sunday, March 11 at 7:00 p.m. ET/PT.

Today, Khan reaches over 4 million students across the world each month. They visit Khan Academy to learn - at no charge - from the thousands of video lectures on school subjects, featuring just his voice and the diagrams he draws. Not showing his face is one of the secrets to his effectiveness, says Khan. "Look, if there's a human face, especially a funny-looking human face, then it's actually hard to focus on the math," he tells Gupta. And it's easier for the teacher, too. "I don't have to shave...comb my hair. I just press record, make a video," says Khan.

It all began in 2004 when he agreed to tutor his cousin in algebra and eventually wound up posting tutorials on YouTube. Others began to find the video tutorials and it became more than just math, as Khan, then a Harvard and MIT-educated hedge fund analyst, branched into other subjects. As popularity grew, he became inspired. "I started getting feedback... 'my child has dyslexia and this is the only thing that's getting to him.' I got letters from people saying...'we're praying for you and your family,'" he tells Gupta. "Pretty heady stuff." So, he quit his job and began working out of his closet in a non-profit endeavor to "provide a free, world class education for anyone, anywhere."

Then, Microsoft Chairman Bill Gates discovered Khan's videos for his own kids; he invited Khan up to his foundation to discuss Khan Academy. Soon, millions of dollars were donated to his efforts, much of it from Google and the Gates Foundation.

Khan Academy is now even more effective than it was before the infusion of cash, when it was mostly Khan's skill at simplifying classroom problems for individual students. Now, schools are using Khan Academy with the aid of a "dashboard" Khan's staff created that monitors the real-time progress of individual students. This feature lets teachers find and teach the stragglers before they fall too far behind. "I can track their progress...I can see who's rushing ahead, who's lagging behind," says Courtney Cadwell, a teacher at the Egan Junior High School in Los Altos, Calif. "I feel I am using my time more effectively."

This measurement of progress could be a breakthrough, says Eric Schmidt, the chairman of Google, who tells Gupta that innovation never comes from the institutions themselves, but rather from visionary figures outside those institutions. "Sal is that person in education in my view. He built a platform. If that platform works, that platform could completely change education in America," says Schmidt.