Screenshot of Khan Academy iPad application.

Sal Khan and his team at Khan Academy have a class — or roughly 3,000 classes — you might want to take.

Okay, maybe you don’t want to take all of those classes, which could take years to get through (and not all of us need or want to prep for the GMAT). But Khan Academy’s YouTube video class database, which launched on the iPad on Sunday, gives any individual with a computer and sufficient Internet connection the opportunity to receive instruction on a variety of subjects, assuming they find the format and content of the classes palatable.

All the classes are taught by the site’s founder and executive editor, Salman “Sal” Khan, who brings a conversational tone to each of the videos. Unlike for-profit educational institutions that offer online classes for a fee, Khan Academy is a nonprofit group that offers all its classes free of charge, thanks in large part to big donors such as the Bill & Melinda Gates Foundation and Google. (In the interest of full disclosure, my brother works for Google.)

This free access, combined with the breadth of the topics covered and conversational tone of the lessons, provides an accessible alternative to the traditional classroom on a number of complex subjects students traditionally struggle with, such as science and mathematics.

Sal Khan, founder of the Khan Academy, in 2010. (Courtesy of Khan Academy)

The iPad app, meanwhile, gives users the opportunity to download videos for offline viewing and jump through videos by navigating subtitles. Users can also log into a Khan Academy account to track their individual progress and receive credits for watching videos — making the learning experience like a game. The app is, as of the writing of this post, the sixth most popular free app in the iTunes store and the top app in the education section, with roughly 17,500 downloads since it was made available Sunday morning, according to a Khan Academy spokesperson.

Exercises, while not included in this version of the app, will be “coming soon,” according to the description on the Apple Web site. As Fast Company’s Greg Ferenstein observed Sunday, the Khan Academy iPad app is potentially significant in that it could cut into the cost associated with textbook purchases.

Khan, a former hedge fund analyst, started by posting math tutorials in his spare time on YouTube in 2004. In 2009, according to a July 2011 report by Wired’s Clive Thompson, Khan started making lessons full time with a donation from Ann Doerr, the wife of Silicon Valley investor John Doerr. Microsoft founder Bill Gates soon became a fan, casting a spotlight on Khan and his work.

CNN’s Sanjay Gupta reported on Khan Academy in a segment for CBS’s “60 Minutes” on Sunday, highlighting how its videos and teacher resources, which give instructors tools to monitor student progress, are being used in classrooms primarily in the wealthy Silicon Valley suburb of Palo Alto.

But Khan Academy isn’t a welcome development for everyone, particularly among members of the educational establishment, as The Post’s Steven Pearlstein outlined in a May 28 column.

Khan is not a trained teacher. So, for those invested in a system built on teacher training requirements and national standards, Khan Academy could be seen as a threat, if not an entirely superficial development. Also, although the lessons and content on the site are free to use, the hardware needed to use them is not — a potential burden for cash-strapped individuals and institutions.

But, in a June 3 interview with The Post’s Hayley Tsukayama, Khan took an opportunity to respond to some of criticism, saying, in part:

Most of the criticism I’ve heard is from people who are looking at it too superficially, making a shallow judgment. Some haven’t even seen one of our videos.

What do you think: Is Khan Academy education’s future, or does it fall short?

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