Over the past decade, the free instructional website Khan Academy has transformed how tens of millions of students across the globe perceive and approach math. Now, it’s pursuing a bigger aim: ...

(CBS News) Sal Khan is a math, science, and history teacher to millions of students, yet none have ever seen his face. Khan is the voice and brains behind Khan Academy, a free online tutoring site ...

Corrected: An earlier version of this story incorrectly stated the number of registered users of the Khan Academy. It is 137 million users. A bevy of technology and software tools are taking center ...

The following script is from "Teacher to the World" which aired on March 11, 2012, and was rebroadcast on Sept. 1, 2013. Sanjay Gupta is the correspondent. Denise Schrier Cetta, producer. Take a ...