(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 ...

Eastern Kentucky University’s Chemistry II summer course was no picnic: Tough concepts and lectures chock-full of technical content regularly vex students. But physics/astrophysics major Wendy Brock ...

All products featured here are independently selected by our editors and writers. If you buy something through links on our site, Mashable may earn an affiliate commission. Khan Academy's math lessons ...

Watching videos online usually means goofing off. But over the past few years, millions of decidedly enterprising people have turned on their computers to watch, of all things, math and science ...

"This," says Matthew Carpenter, "is my favorite exercise." I peer over his shoulder at his laptop screen to see the math problem the fifth grader is pondering. It's an inverse trigonometric function: ...

Studying and learning at your own pace online is offered at Khan Academy that is next on our list of free math classes for adults in NYC. You can find practice exercises, instructional videos, and a ...