Why are you doing this project?

I (Sal) can't imagine a better use of my (or anyone's) time.

With just a computer and a pen-tablet-mouse, one can educate the world! Even better, the content never goes old. My (or your) great-great-great grandchildren could learn from the very same videos!

What do you think makes the Khan Academy different than all of the other educational resources out there?

There are some obvious distinctions. With over 2800 videos, it is easily the most exhaustive collection of instruction on the internet allowing learners to know that they can fill in almost any of their "gaps" with the content on this site. The content is made in digestible 10-20 minute chunks especially purposed for viewing on the computer as opposed to being a longer video of a conventional "physical" lecture. The conversational style of the videos is the tonal antithesis of what people traditionally associate with math and science instruction. The less obvious distinctions are, however, what make the site hard to reproduce.

I teach the way that I wish I was taught. The lectures are coming from me, an actual human being who is fascinated by the world around him. The concepts are conveyed as they are understood by me, not as they are written in a textbook developed by an educational bureaucracy. Viewers know that it is the labor of love of one somewhat quirky and determined man who has a passion for learning and teaching. I don't think any corporate or governmental effort--regardless of how much money is thrown at the problem--can reproduce this.

A lot of my own educational experience was spent frustrated with how information was conveyed in textbooks and lectures. There would be connections in the subject matter that standard curricula would ignore despite the fact that they make the content easier to understand, enjoy, and RETAIN. I felt like fascinating and INTUITIVE concepts were almost intentionally being butchered into pages and pages of sleep-inducing text and monotonic, scripted lectures. I saw otherwise intelligent peers memorizing steps and formulas for the next exam without any sense of the intuition or big picture, only to forget everything within a matter of weeks. These videos are my expression of how the concepts should have been expressed in the first place, all while not compromising rigor or comprehensiveness.

What curricula are you following?

The simple answer is none. I believe that someone who truly understands the core concepts will thrive academically regardless of the curricular context. To take it a step further, I believe that someone who experiences the joy and satisfaction of true understanding will never again be satisfied with the superficial type of learning that most students have grown accustomed to. The Khan Academy is about placing deep understanding above anything else.

With that said, there are concepts covered on national examinations that any student needs to be exposed to in order to be competitive. That is why I try to cover all topics that would appear on A.P. tests, SATs, and other standardized tests. Taking it a step further, there are several hundred videos devoted to SAT, GMAT and other standardized test problems. I also believe that, because of the granular nature of the 10 minute videos, the content can be mapped to almost any state's or nation's standards.

How do you know that the Khan Academy is effective?

My background is in math, computer science, and investment management, so I think you can imagine that no one is more obsessed with data and analytics than me. The chart to the right is provided by YouTube. It can be used to determine if and/or when viewers' attention falls off at a certain point of a video. I can then go back and try to identify (and possibly fix) what happened at that point in the video.

The next chart shows the average (black line) progress of a cohort of 30 rising 8th graders on the Khan Academy software over a 6-week period. The horizontal axis is "days working on the site" and the vertical axis is "modules completed." The green lines show one standard deviation above and below the mean. This chart exemplifies both the level of data we are capturing and also highlights the importance of individualized, self-paced instruction and real-time assessment. The purple line shows a student who may have been deemed "slow" by traditional assessments because she was more than one standard deviation below the class average after working on the site for a few days. The reality is that she just needed more time ramping up on negative numbers than the other students in the cohort. Once she was given the chance to become proficient on that concept, she raced forward and ended up being one of the top students in the cohort.

More than the data, however, it is the anecdotal evidence from users that has convinced me to quit my job and make this the focus of my life. I receive hundreds of letter and comments a week. Many are simply notes of strong appreciation, but several reach the level of being genuinely inspiring. Here is a letter I received from a YouTube user in September 2009 (I bolded some of the text):

Mr. Khan,

No teacher has ever done me any good--this may sound harsh but I mean it quite literally. I was force fed medication to keep me from talking and chastised for not speaking out when called on. Where I am from blacks are not welcomed with open arms into schools--my mother and her sisters had to go to a small shack two hours from home when they went to school. About five years ago my family collected enough money to move from where i was born, so that I could have a chance at having an education and living a real life. But without a real mastery of elementary math I was slow to progress.

I am now in college and learning more than I ever have in my life. But an inadequate math background has been holding me back. I found the Kahn Academy in June of 2009, right after I completed Math 141 ( a college algebra course). I have spent the entire summer on your youtube page. And I just wanted to thank you for everything you are doing. You are a Godsend. Last week I tested for a math placement exam and I am now in Honors Math 200. No question was answered incorrectly. My placement test holder was so impressed by the breadth of my knowledge of math that he said I should be in Linear algebra.
Mr. Khan, I can say without any doubt that you have changed my life and the lives of everyone in my family.

I wish you and the Khan Academy the best of luck.

I'm a teacher trying to set up Khan Academy in my classroom or a parent trying to sign up my child. How do I start using this with my student(s)?

Check out the Getting Started page for details.

How did you get started?

My uncle's family visited me in Boston after my wedding in the summer of 2004. At some point during the trip, my Aunt told me that her daughter (my cousin) was having trouble with "unit conversion" which was not allowing her to be placed in the more advanced math track for 7th grade. Nadia was clearly a very bright girl, so I made a deal with her. I'd remotely tutor her for an hour after work as long as she was willing to do any extra work I gave her.

I began remotely tutoring Nadia in August of 2004. She was in New Orleans--where I also grew up-- so we used a telephone to talk and Yahoo Doodle as a shared notepad. Nadia ended up catching up and getting ahead of her class so I started tutoring her brothers, Arman and Ali, as well. Eventually, word got around and I was remotely tutoring and handful of cousins and family friends. Scheduling around my work, their soccer practice, and the different time zones became a little ridiculous, so I started to make YouTube videos for them to watch in their own time, at their own pace.

It didn't take long to see that other students (including adult learners) were hungry for videos like these so I kept going!

Even before I made the videos, I started writing simple Javascript problem generators so that my cousins would never run out of practice problems. I wanted to know when and how they were doing the problems, so I added a database to track usage. 100 modules and thousands of lines of code later (much of which has made the software adaptive), it has morphed into the adaptive assessment exercises on our site.

How did you have the time to do this while working full-time?

My wife was doing her residency--in internal medicine-- from 2005 to 2008, so there were many nights/weekends where she was working and I would have felt guilty doing anything less productive. I also try to watch very little television. On top of that, I was working at an investment fund that had me working 5am to 2pm (we were working East Coast hours from California) so my afternoons were free (although I did go to bed at 9).

My school/district/country blocks YouTube or I don't have an internet connection where I want to use the site. Is there any other way to access the content?

All the videos are mirrored at archive.org, and if YouTube is blocked for you the site will automatically fall back to show you the copies from there. The Lewis Center for Educational Research which is affiliated with NASA is bringing the content into community colleges and charter schools around the country. World Possible is creating offline snapshots of the content to distribute in rural, developing regions with limited or no access to the Internet. One can also download the content off of YouTube for free using the latest version of RealPlayer, or in bulk from several other sources.

How are you funding/making money off of this?

I quit my day job as of September 2009 to work on this full-time and was digging into my savings until recently. In May 2010, some generous individuals gave large enough gifts for me to take a salary.

Since then, Khan Academy has received donations from The Gates Foundation and won Google's Project 10 to the 100 of ideas to change the world.

Khan Academy is an IRS-recognized 501c3 not-for-profit organization. My goal is to make it self-sustaining in the next five years.

Are you interested in turning this into a business? Maybe with some VC funding?

I've been approached several times, but it just didn't feel right. When I'm 80, I want to feel that I helped give access to a world-class education to billions of students around the world. Sounds a lot better than starting a business that educates some subset of the developed world that can pay $19.95/month and eventually selling it to some text book company or something. I already have a beautiful wife, a hilarious son, two hondas and a decent house. What else does a man need?

With that said, if you are a social venture capitalist and are looking to deploy capital with the highest possible social return per dollar invested, we should talk. I think you'll find that there is no more measurable, scalable and high impact way to educate the world.

Did you do all of the videos?

As of today (10/27/2011), the vast majority of the 2800+ videos have been made by me. Recently, we partnered with Smarthistory, and Dr. Beth Harris and Dr. Steven Zucker have joined our faculty and added hundreds of Art History videos to our library. Volunteers have also begun to translate the videos into other languages. Here is the Khan Academy en espanol. Hope to have other channels in the not-too-far-off future!

Can I dub your videos in another language? How do I go about doing it?

Absolutely! In fact, the Khan Academy’s translation project is looking for passionate individuals like yourself who can translate the tutorials into the world’s widely spoken languages. If you can offer consistency in voice and quality across topics, we will feature YOUR translations on the Khan Academy website! Visit the translation project for assistance and updates.

What topics do you plan to cover?

My goal is to cover everything. Yes, everything! Most of k-12 math has already been done. My goal really is to keep making videos until the day I die (which will hopefully not be for at least another 50 or 60 years). Should give me time to make several tens of thousands of videos in pretty much every subject.

What is the long-term goal for the Khan Academy?

I see Khan Academy becoming the world's first free, world-class virtual school where anyone can learn anything--for free.

The videos are just part of the vision. We are building out the adaptive software to cover all the topics that the videos cover. We also intend to develop simulation games to give more nuanced and applied understanding of concepts.

What equipment do you use to make your videos?

I use Camtasia Recorder ($200) + SmoothDraw3(Free) + a Wacom Bamboo Tablet ($80) on a PC. I used to use ScreenVideoRecorder($20) and Microsoft Paint (Free).

Where are you from? What ethnicity/religion are you?

I was born and raised in New Orleans, Lousiana. My mother was born in Calcutta, India. My father was born in Barisal, Bangladesh.

If you believe in trying to make the best of the finite number of years we have on this planet (while not making it any worse for anyone else), think that pride and self-righteousness are the cause of most conflict and negativity, and are humbled by the vastness and mystery of the Universe, then I'm the same religion as you.

How can I/you help?

See the How to help page.