University of Miami education professor Walter Secada, who specializes in how math is taught, praises Khan's personable style. But while Secada says the Khan videos he reviewed are accurate, he's concerned about how Khan uses an example to define a term, rather than defining the term more generally. Secada says he can envision some students becoming confused when having to apply a concept to a different example.
"It may seem like a small point but it lays a foundation for later problems," Secada says. "That's the strength and the weakness of this. In an eight-minute video, you can only do so much."
YouTube's potential for instruction is one reason Internet search leader Google Inc. bought the video site for $1.76 billion two years ago. Google founders Sergey Brin and Larry Page realized that certain search requests could be better fulfilled with how-to videos than with written explanations. But they didn't have a good way of filling that need until YouTube landed in their laps. Now Google includes YouTube videos when it delivers search results.
Not all tutoring videos on YouTube are created equal, however.
Central Florida sophomore Jacqueline Boehme found that out quickly when perusing biology clips. Some had poor video quality and were blurry or too small.
"There are definitely some that are better than others, so it's always useful to look at a few," says Boehme, who has looked up videos that explain processes like protein synthesis. Boehme says the 3-D representations have helped her conceptualize what she's learning in class.
Secada would like to see math faculty incorporate some videos in their teaching, or recommend clips that have been vetted. He cautions students not to depend solely on what they find online.
"There's a point at which kids do need to double-check with their textbook" and professor, Secada says. "Before you need to quote this in your test, you need to look at this and check if it's right."