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How well does Khan Academy teach? (washingtonpost.com)
163 points by ColinWright on July 27, 2012 | hide | past | web | favorite | 111 comments



I spend a lot of my time in outreach, enhancement, and enrichment activities, and I've now met several people who have taken to watching lots of the Khan videos. Some of them are doing spectacularly well, possibly partly because of them, although correlation versus causation, etc.

However, I have had some seriously worrying conversations with people who have some deep, deep misconceptions, and who believe they have been vindicated by some parts of some of the videos. Again, correlation versus causation, etc., but some of the things these people believe they've learned from the KA, and believe must be right because they (think) they've seen it on KA really worry me.

I agree with Sal when he says:

    We believe that we are in the early days of
    what we are and feedback will only make that
    better.  I agree with you that no organization
    should be upheld as a magic bullet for education
    woes.
However, part of that feedback will rightly be negative, and some of the fanboi-isms I see worry me almost as much as some of the misconceptions I see.

It's a brilliant body of work, certainly ground-breaking, and potentially revolutionary. But it has its problems, and denying that doesn't help.


> some of the things these people believe they've learned from the KA, and believe must be right because they (think) they've seen it on KA really worry me

What kind of things?

Are you suggesting that flesh-and-blood teachers or brick-and-mortar schools are less likely to spread misinformation or leave students with misconceptions? I can tell you a hundred false things I was taught by "real" school, and some of them are probably just things I think I was taught.


Truly the greatest enemy the online education revolution faces is not the current education system, but the way that people secretly substitute the real system for this mysterious magical perfect system based on the assumption that the stated goals of the current system are actually its result, and compare online against the myth instead of the reality.

Goals aren't results. Compare real to real. The real competition isn't the mythical fantasyland where everybody learns everything perfectly and retains it forever as a result of the gentle teachings of the schoolmarm. The real competition is the system that produces the real people you really run into as you go about your day, doing real things. If online education in its currently very early state even manages to sometimes match the real world, at one-tenth the price or less, you can imagine what another ten or twenty years of refinement is going to produce for the online model.

And in that real comparison, online will definitely not always win today, and will always have weaknesses. Shop class seems unlikely to work well online. (But then, the real school systems shut down those classes 20 years ago....)


This is a spectacularly true comment, and is generalizable across disciplines. I've rewritten it slightly to generalize it....

Truly the greatest enemy the $REFORM_MOVEMENT faces is not the $EXISTING system, but the way that people secretly substitute the real system for this mysterious magical perfect system based on the assumption that the stated goals of the current system are actually its result, and compare online against the myth instead of the reality.


This. And I spent some time in some of those education courses they (sort of) recommend to Khan in the article, and they were either a complete waste of my time or worse. They have more bad politics than good pedagogy.


Are you suggesting that flesh-and-blood teachers or brick-and-mortar schools are less likely to spread misinformation or leave students with misconceptions?

Possibly, because when you leave school you can realize your misconceptions and learn from other people, as well as pointing out other people's misconceptions. But if everyone uses Khan Academy, everyone will end up with the same misconceptions.


Except the self-fixing process you claim to be characteristic of physical institutional learning only happens when there is a significant number of people in the class that are A) In a position to think confidently and critically about the material B) willing to invest time and effort (often lots of both) in finding the correct conclusion and C) in contact with you about their insights. I have found the confluence of those factors to happen exceedingly rarely in physical classes and significantly less rarely in hybrid physical/online classes. This isn't surprising because lectures place severe limitations on two-way communication that online environments don't. With a traditional class structure (lecture/discussion section) I suspect at least 3/4 of questions go unasked and at least 3/4 of the received answers never get shared beyond the immediate group of individuals doing the asking (in comparison to an online forum, where the answers are googleable or at the very least spread to the entire class).

Also, online learning wins in the limiting case where courses have been iterated and feedback / FAQs taken into account. In a brick and mortar institution, "institutional memory" is effectively lost as professors retire or shift interests (if it ever existed in the first place) and their replacements introduce their own slew of idiosyncrasies, poor methodology, and misconceptions. In contrast, an online lecture never suffers this degradation. Sure, new lectures may replace old lectures (presumably at different sites), but both will be available for a time and during that time, students will pick up on inconsistencies. That's not true of brick-and-mortar lectures, where the only source by which a student can verify the material they are presented is the textbook or its alternatives. Combined with the tendency of courses to discourage reading the textbook (it's almost always a less point-efficient use of time to read textbook chapters than to do homework, practice problems, and go to office hours, which provide information better matched to the material that will be tested on), the status quo is a recipe for failure. My experiences confirm that this recipe for failure produces failure (in the pedagogical sense).

The third factor that favors online learning with regard to misconceptions are its twin killer features: the pause button and the rewind button. These reduce self-inflicted misconceptions tenfold.

So, sp322, I think the opposite of what you stated is true. I would welcome a conflicting opinion, because usually when I go on rants similar to the above three paragraphs all I get are nodding heads.


Why wouldn't you be able to do that after taking some classes online?

I guess some people are suggesting that Khan Academy is the ultimate in education and that everybody should use only that and nothing else?


Yes, lets just perpetuate mistakes in perpetuity. And I highly doubt everyone would end up with the same misconceptions. However, the fact that Khan Academy is a) not rigorous, b) has no type of human interface with the teacher, c) has no type of input from professors and lead academic institutions, d) is purported as an educational savior by influential people when there is no such thing, e) uses outdated and confusing teaching techniques, f) has yet to put problems over exercises, and g) has no type of human interface between students it has a long LONG way to go.


Why must we always jump from A to B? I see this happen in all contentious subjects, but nowhere more than in education discussions.

The top-poster's point was about a very specific type of problem he's seen with some people watching some of Khan's videos. He does not even hint about the prevalence of the same problem in traditional schools.


Derek Muller of the YouTube science channel Veritasium did a TED audition wherein he discussed this: http://talentsearch.ted.com/video/Derek-Muller-The-key-to-ef...

He found that just showing a video of the laws of motion made people more confident of their answers on a physics quiz, but just as wrong. They would actually have false memories of the video confirming their prior knowledge. What worked was first debunking misconceptions and then replacing them with the truth, even though those videos were rated much more confusing.

We're not teaching blank slates, and if you teach as if you are, you end up with what you (and Derek) described.


Fascinating. There is also research showing (in gossip/news and politics) that by refuting a false statement, the act of repeating the statement actually reinforces it. People ignore the "... IS FALSE" part. I think that plays in here --- my simply consuming a statement, they slightly edit it to fit in with their prior information, or just to make it easier to remember, by dropping the complications.

You need to to drag someone through the mental struggle of unseating their beliefs.

My favorite technique is to find the source of the misconception, and highlight it. Instead of attempting to dispose of an entire complex thought, pick it a part, find the mistake ("you are confusing 'velocity' and 'force' -- they are different things."), and rebuild the correct explanation using the patched piece.


I think that the crux of the argument seems to be this idea that there is a "magic bullet" to fix the education system. As a former teacher I can tell you that if there is a magic bullet it's parent involvement in students lives. No textbook, online video, or even a fantastic teacher is an acceptable substitute for parent involvement as a foundation for a child's educational success.

With that said, I think that KA is an excellent addition to the pieces of the educational puzzle. I've used many of his videos to supplement teaching and textbooks, both good and bad.


I agree. There is no doubt that Khan Academy is revolutionizing education, but it revolutionizes most and above all teaching, not learning. It enables students and teachers alike to get access to a wealth of instructional materials at any time, any place. It gives a second perspective on the material under study. It allows those that have forgotten a lot of the material to pick up again fast. It enables teachers to turn traditional lessons around: in stead of instruction in class and homework at home, one now start thinking about delivering instruction at home and do problems in the school environment.

At the same time Khan Academy's video lectures cannot take into account the prior knowledge of students but for what other videos have been downloaded at Khan's. It cannot take into account students' background, wishes, problems, disadvantages, and so on. There is no interaction, there is no conversation going on between teacher and pupil, pupil and pupil, and in the social environment of a class.

Furthermore, most videos and exercises seem to focus on repetition, rote learning, and giving correct answers. There is no room for exploring alternatives, errors, hypothetical situations, and what not.

Over-all, and most importantly, I wonder if Khan Academy does support/instigate/promote deep learning of the topics covered. And is that actually possible the way Khan Academy is set up?

Observe that Khan himself doesn't claim nor suggest so, but many who hail Khan as the savior of education seem to equate education with learning and, as a result, claim Khan's revolution in education as a revolution in learning. To me, these aren't the same and this pollutes the discussion between educators and fans.

To summarize: I think Khan's revolutionizing education but he isn't revolutionizing learning


I have similar second-hand experiences, but really I'm not sure it's different than any other self-study method in that regard. I know people who are doing spectacularly well in things they self-taught from textbooks and online materials (FAQs, tutorials, StackExchange answers, etc.), and other people who have quite serious misconceptions they've somehow picked up in that route.

Khan Academy is interesting to me not really because it's a revolution in learning, but because it's another modality that is better for some people. Some people learn well from written material, and those people have traditionally been the successful autodidacts, working their way through textbooks and tutorials. But perhaps different kinds of materials can cater to other people, with people working their way through a lecture series instead of a textbook. That'll probably have many of the same pros and cons.


You say that, but I think a lot of people are making up criticisms in order to justify ignoring it.

Where i was taught we still had the exact same decimal problem khan has...

The best way to deal with it is through continuous refinement until criticisms are few


  > The best way to deal with it though is
  > continuous refinement until criticisms
  > are few
And for that you need the criticisms.


I regularly find that the criticisms you see launched across the internet at various projects are a lot less worthy than the criticisms that they generate internally. I'm of the mind that if you believe that something is valuable or worthy you should criticize it because that is how it will improve. And as such I quite look forward to reading criticisms exciting new projects like say Wikipedia or Khan Academy.

I am, almost without exception, deeply disappointed by the knee-jerk reactionary defensiveness you generally find in these things. Conversely, you go visit Wikipedia itself and it has insightful comments about how its user base tilts the content away from the global south, women, the poor etc. and constructive ideas for how to measure and ameliorate such issues.

I think it's only natural for people to react to such uninformed, accusatory criticism in the way they do. It reminds me of John C Dvoraks anti-Mac columns from years ago, which he later admitted were professional trolling.


I've watched some of the math videos with my 11yo. There's definitely room for improvement, but I find that encouraging. It's nice not to be close to the ceiling of how good online education can be.


I'm really starting to believe that these "critiques" of Khan Academy are just teachers and professors terrified of becoming irrelevant.

The question shouldn't be "How well does Khan Academy teach" (well, maybe someday). The important question right now is "Is Khan Academy a better learning tool than most high school and college teachers?". In my experience, the answer overwhelmingly is "yes".

I did have some truly fantastic teachers/professors on the way to a STEM degree, but they were rare. Most were terrible to mediocre, even at a semi-prestigious university. Khan Academy has greatly reinforced my understanding of some subjects, and it's been exceedingly easy to learn some new subjects.

So yes, it doesn't stack up to the top tier teachers and probably never will. But that doesn't matter, because there aren't all that many fantastic teachers and Khan Academy is better than the rest.


I'm really starting to believe that these "critiques" of Khan Academy are just teachers and professors terrified of becoming irrelevant.

I try not to ascribe unstated motives to people, but I really wonder at the smell of pedantry and elitism in an article like that.

Khan offers a free educational service that is very popular. That is a Good Thing(tm)... PERIOD.

People are logging in to his site to learn things. Khan has created a whole model for learning online that has some people enthusiastic about learning more than they could by sitting in class -- yet the criticism from this article is that the Khan videos aren't ideal in using the latest buzz-wordy techniques approved by academia?

Maybe the authors of the articles/papers could interact with Sal Khan and offer help. Or if the authors really felt strongly about their qualifications vs Khan's, maybe they could offer free online teaching videos that were more "correct".

This type of headline sensationalism designed to take down someone doing a good thing is just sad.


> Khan offers a free educational service that is very popular. That is a Good Thing(tm)... PERIOD.

Yes, because when something is popular and free, its got to be good. cough religion anyone cough.

If that is considered to be the measure of quality these days, our society is doomed. Education is an important thing, ignoring it and treating this one man as some "messiah" of education when he clearly introduces wrong and obtrusive concepts for the sake of "getting it out to the masses" is not education.


Besides learning about his project online, I don't have any use of or interest in Khan Academy. There's no religion on my part, just a little disgust that a for-profit company would try to smear KA over minutia.

It would be like if Khan Academy was giving out free meals to homeless people and McDonalds fabricated reports on how the food was unhealthy and used their influence to get the Washington Post to carry the smear and add to it.

wrong and obtrusive concepts

Now who is showing a religious level of bias?

I'm a pragmatist. If something is free that I need, I use it. If something is for-pay that I need and the price is justifiable, I use it. My commercial software architectures often mix proprietary and open source solutions and I don't make excuses for either business model.

One thing about free, you can always get a refund on your investment and you have to really suspect the motives and the character of someone who attacks "free". Not real surprising that the attacker in this case was a for-profit competitor, was it?


I don't know if we are talking about the same article, I'm talking about this one "How well does Khan Academy teach?" by the Michigan University math prof who outlines, in detail, basic concepts like adding decimals and multiplication that are taught at Khan Academy in a way that goes against research.

There is no religious bias, its a difference between a ineffective and wrong way vs. an effective right way. The professor performed no smear against Khan Academy, but the fact he only saw two videos that cause confusion in basic math concepts, it should make one skeptical, especially when someone like you justifies it on the basis of popularity, pragmatism and "minutia".

It seems like you read one article from the Washington Post that wasn't written very well and from that one article, deduce that WP is on some smear campaign. Absurdity of the highest order.


Totally agree with this.

I've just finished a BSc Physics-Math at a UK "Top 20" University. The standard of many lectures was very poor with only a few exceptions.

Without Khan Videos I wouldn't have grasped many of the concepts. (The lecturers often presented the formalism without really going into the concepts - I often wondered did the really understand the material themselves)

Apart from online material the only other self-study stuff I found useful for the degree were course books from Open University (OU). Excellent stuff.


A good teacher will never become irrelevant. A bad teacher will become more effective because they they don't waste time with bad lectures. I also think it would be easier to help individuals with problems rather than dealing with the varying abilities of a group of students at the same time.


The PC wasn't better than the mainframe at everything. It didn't have to be. That's how disruption works.

Many good instructors can't draw a line between KA (or any other disruptive solution) and the absolute best, gold standard, scientifically-proven best way to teach (usually their favorite methodology).

The fact is that he's better than most of the teachers out there. It's a rising tide: if your teacher has a Presidential Award for Excellence in Mathematics and Science Teaching you probably don't need Sal Khan.


The main criticism of the article is a bit silly:

Khan will put the video out there and see how people react to it. He perceives this to be a better approach than incorporating results of quality research projects into his instructional decisions. In the age of No Child Left Behind and its mandate for “scientifically based research” as the foundation for classroom instruction, this seems lazy.

Yes, Khan is doing his own scientific research, on the theory that he does a better job than the educational establishment. This might be arrogant (given the quality of educational research I've seen, I don't think it is), but it isn't lazy.

As for the claims that Khan does a worse job than other teachers, no data is provided to back this up. Just vague claims that if he did something different, he might get better results.


I don't think so at all. The author supported their claim with that indicate Sal Khan doesn't fully recognize the impact of PCK, and gives specific examples in Khan's lessons.

While PCK is a "buzzword", it does represent something very real in learning: That Instructors (be they amateur or professional) must understand the hidden challenges of the material they teach. Specifically, in ensuring that misconceptions do not propagate and embed themselves into a pupil's mind. In math, misconceptions can be particularly troublesome as the facets of mathematics, particularly at the elementary level, carefully layer on top of each other.

If you want an example of this that falls into the sphere of stuff closer to HNs, look to Zed Shaw's Learn Code the Hard Way series.

Shaw puts exercises and examples in front of readers designed explicitly to prevent the reader from developing weird misconceptions about the way a programming language (or programming in general) works. That's often why readers will say things finally "clicked" when they work through his material. Shaw may not be familiar with the buzzword term "PCK" but he definitely recognizes the challenges in teaching each concept he presents to the reader. You can see part of this come through with his critique of K&R C.


But just "putting the video out there and seeing how people react to it" isn't "scientific research." Science involves testable hypotheses and controlled experiments. Just throwing things against the wall and seeing which ones stick is something different.


"Putting the video out there" is an experiment. It's not rigorously controlled, but it's about as controlled as a website is likely to get. So they put something out there, see how well it works, and maybe tweak it.

That's the very essence of scientific experiments. You don't always need a "hypothesis" to do science. (Or, if you like, the hypothesis is "This video will teach students to do X.")


Khan has a fairly extensive testing/data analysis system. He puts the material out there, measures whether students correctly answer the problems, and iterates from there.

While it's not controlled experiments, it's about as close as you can get in education.


Meant to reply to this, but didn't work, so copying and pasting:

In the debate about khan academy, there's an important fact that is continuously missed, it's not about effective instruction vs. ineffective instruction; it's about less effective vs. more effective.

The khan academy way may be better than trying to learn from the lower X% of math teachers out there. It's highly unlikely that it's going to be better than the top Y%.

Things like Khan academy will not "fix" education. Anything that standardizes and automates education will only do one thing: insure mediocrity. It will protect against the bad while eliminating the possibility of excellence.


The problem with education in the US is cost - quality is almost as good as it possibly could be (holding the inputs fixed).

In 2010, the US government spent $900B on education. If Khan can reduce the number of teachers needed by even a few percent, that's a HUGE savings.


In 2010, the US government spent $900B on education. If Khan can reduce the number of teachers needed by even a few percent, that's a HUGE savings.

Fully agreed with the conclusion. Staff compensation (including SUBSTANTIAL nonsalary compensation) is a big part of the budget of any school. Making the work of teachers more efficient (in the economics sense of "efficient") helps free up money for other worthy purposes.

Another comment to your comment doubted the figure, I think because you wrote "US government spent" when you perhaps meant "all levels of government in the United States spent" so much money on education. Most spending on schools in the United States is from state taxes (as in my state) or from local taxes (as in some other states), as I'm sure you already know but which may be news to onlookers from other countries.

"The U.S. has more than 14,000 public school districts and spends more than $500 billion on public elementary and secondary education each year (combined spending of federal, state, and local governments)."

http://www.census.gov/did/www/schooldistricts/

"United States

(Billions of dollars. Detail may not add to total due to rounding)

Total Federal State Local

593.7 74.0 258.2 261.4"

http://www2.census.gov/govs/school/10f33pub.pdf


in 2010, the US Department of Education budget was $47 billion [1]. That's between 1-2% of the total budget. The problem with education in the US is not cost, and even if it was, the solution is not 'get rid of a few percent of teachers."

Where did you get that $900 billion number?

[1] http://en.wikipedia.org/wiki/2010_United_States_federal_budg...


This doesn't include state and city levels, where most of the education spending happens.


This article is a critique of the traditional aspect of teaching (having a teacher lecture students). This is obviously important, so it's good to have professional educators provide feedback.

However, I thought the aspects that was supposed to be "revolutionary" was detailed tracking and analysis of students and that feedback loop (either back into the system, to the student themselves or to teachers). They seem to completely ignore this.

Khan Academy isn't disruptive because of Salman Khan's lessons. It's disruptive because of the underlying platform, which any teacher (some possibly better than Salman) or any student could take advantage of.


I found the examples the article gave about students' common misconceptions interesting. I'm wondering whether the tracking and analysis by Khan Academy picks up these misconceptions as well. For example, in one of the examples (8 + 4 = _ + 5) many students answer 12 or 17. Khan Academy should be ideally placed to find such misconceptions if only because their sample size is much bigger than the average classroom.


"Khan Academy should be ideally placed..." I would say 'yes' and 'no' to this. Yes if the questions ask, and no if they don't. And that's the point of the piece. Khan won't pick up these misconceptions because he doesn't ask. He doesn't ask about decimals with different numbers of decimal places; he doesn't ask about the meaning of the equal sign. Maybe it's because he doesn't know that he needs to ask these things. That is a kind of knowledge he didn't need in his old profession and that he does in his new one. Maybe as KA grows, he will improve on this point and he will bring in people with this knowledge. But given Khan's dismissive ness of education research in the Harvard EdCast interview, I am skeptical.


I think one of the most groundbreaking ideas they have is "flipping the classroom" [1], where students watch Sal's videos at home before class for homework, then in class they work on problems with the teacher and other students. That's where the ability for teachers to track and target deficiencies really becomes powerful.

[1]: http://www.usatoday.com/life/people/story/2012-05-30/sal-kha...


I have seen this firsthand in Massachusetts and it was very powerful. The kids were all clustered around iPads or Macbooks, helping each other, doing problems, and reviewing what they learned for homework. The teacher was rotating around the room, helping stuck kids, encouraging others to do peer-to-peer coaching, etc. It was so absurdly different than how I "did school," yet so logical. The teacher felt she could now really differentiate her instruction, and the kids were impressively engaged. Gone are the days of 40 minute lectures and 10 minutes of practice— you know, where the kids who got the lecture blaze through worksheets and the rest sit dumbfounded and then take all their problems & questions home for the evening.

All that to say: yes, a dude sketching some problems on a tablet is not the "revolutionary" part (if there is one at all) of Khan Academy.


I agree 200%. It also has a number of other nice side effects such as teaching teamwork/collaboration, etc.


Thousands (millions?) of teachers prepare mostly the same lessons every day. Whilst some preparation is obviously necessary, I see huge benefits for students and teachers from centralising this.

I am looking forward to the future when a video lesson distributed to 20% of children on the Monday can have its feedback aggregated and analysed, with a patched version of the lesson pushed out on Tuesday.

For example, imagine teaching a maths lesson, and seeing that a significant number of children paused and rewatched a particular 20-second section. You could re-film that and splice it in ready for testing the next day. Imagine the possibilities if you had schools offset their holidays by a few weeks!


  > teachers prepare mostly the same lessons every day
That "mostly" hides a lot. A good teacher will prepare this lesson in a context: context of his pupils, their abilities, their knowledge of other material, etc.

Centralized version will have none of that.


I don't see how an individual teacher has the advantage. Most classes have a huge range in ability and any lesson must be suitable for all. A centralised system could (in my dreams) deliver more than one version of each lesson and determine (from their enormous amounts of data) which lesson each child will benefit most from.

Of course if I'm dreaming that much I should point out that with each child able to learn at their own pace a single physical classroom could hold many different levels of the same subject at once, with children from different schools working together...


It is no coincidence that the biggest proponents of this style of learning have strong AI backgrounds. Their vision is a centralized system that can deliver that highly customized material on a per-student basis. It is still early days, but the technology has a lot of room to evolve over time.


So who is making the site that will deliver more personalized instruction? Where is the research that site will use, telling all about which kinds of personalization are proven and how much effect they will have?


One of the issues I have with Khan Academy is that they are using exactly the same style of teaching as in schools...just ported online. Is that really the best way to go about online education?

I find the AcademicEarth.org method of simply filming classes even worse. Yes, they do allow for what you'd normally call "quality education" to be accessible by anyone online, so that's a pretty big step, but I get this feeling that true disruptive online education is supposed to be something more radical...to make things 10x better for learning, not just replicate the offline learning experience.


This is an important point. I've always found lecture to be a very inefficient method of teaching. Why not switch to an entirely written format? You can say a lot with diagrams and pictures. Good exercises and well explained solutions are also very important. Also if it's all text then you can easily search for keywords.


Lectures aren't great, which is why he wants kids to do that at home on their own time (and at their own pace), and use the school day to work on problems and get more individualized help.


I wouldn't call it exactly the same... The biggest difference that frequently gets glossed over is the Coaching interface. In normal schools it's hard to get one-on-one tutoring with someone who can actually help, as well as with someone who knows exactly what you're struggling with. I'm sure most people who've done tutor work have encountered students who can't even describe what it is they're having problems with, they're that far gone.

What improvements do you hope to see? Making it easier to find short-term tutors would be on my list, throw up some IRC channels that tutors can monitor and get notified of students seeking help. I think one-on-one teaching is the most optimal.

As for how easy it is to learn, as long as we aren't hardwiring people's brains with information as seen in The Matrix learning is going to still take work. (Not necessarily hard work in every instance, but work.) I'd like to see more ways to interact and make the knowledge part of one's own experiences rather than as received truth (something Polanyi got mostly right in his Personal Knowledge book). Of course I'm instantly suspicious of any technique or product that tries to oversell its ability to teach concepts faster with better retention, and even more suspicious when it tries to sell itself as "it's so fun the user won't even realize they are learning!" That said, I can see benefits of various systems over both doing nothing and the status quo. Tools like Anki for instance work well, if used. The advice some programming texts give to manually type the programs also has obvious benefits, basically a subset of techniques that train the mind to follow and notice common actions. (There was an app linked on HN a few weeks ago that replicates the motions of solving algebra problems without actually doing any algebra, I can see how "eliminating two like things from both sides" feeling "okay" may help some people a little.) Khan has mentioned that he has offline students watch lecture videos as homework and do problems or answer questions during classroom time, the opposite of the traditional school, I can see its benefits over the traditional method too for classes where information is typically transferred via lecture.

What things like KA, AcademicEarth, and Wikipedia all have in common though is that they change the utility function of learning. That is, when they're not being used as crutches to get through the traditional schools. Students can learn what they want, when they want, stress-free. The classical model is "pass the tests with scores above this threshold or die." (Not literally of course.) It encourages cramming and forgetting. Cumulative testing doesn't help because the course only lasts maximally 9 months (with a big break in the middle), and at higher levels only 3-4 months. Sometimes it's even just one term rather than a full semester. It's not enough. Add in repetition of the wrong things (it's always the most basic things that get repeated endlessly when they're the easiest things to remember!), poor communication between professors of what they actually cover, poor communication between student and professor of what the student actually understands, fixed deadlines, anxiety over money (whether living expenses or paying $1500 for a dumb class), anxiety over spending X hours of your life for a useless class/assignment, retaking the entirety of a class instead of focusing on what you're missing specifically, being forced to take classes one has no interest or skill in, being exposed to one resource, et cetera, it's amazing the classical system works at all.


This article reeks of an academic defending his turf to me. Basically, it all comes down to the author accusing Sal Khan of willfully ignoring research. This is based on a quote that I believe is intentionally misinterpreted. Khan says "you put stuff out there and you see how people react to it". This is basic web testing stuff. That doesn't mean he's ignoring research. Like we don't willfully ignore design best practices with the assumption that A/B testing will sort out the UX. That would be stupid.

I like Khan Academy's videos. But if you watch Khan's TED talk, it's clear neither he nor bill gates sees khan academy as operating outside the education system. His lectures are meant as a complement to quality instruction in classroom by a teacher. Criticizing the Khan academy ecosystem as an independent and parallel instruction system is silly.

Khan is a great lecturer. He's better than every lecturer I've had. He may not be the best total educator. I wrote a blog post about this a while back: http://cyclicreality.com/post/26719449459/why-khan-academy-i...

The hype may be too much. Maybe it's not revolutionary. But getting a teacher who can explain and engage recorded and available free online is a great idea even if it's not the be all and end all of education.


Oh for God's sake. Khan Academy is great complementary source. It doesn't replace schools and teachers. If you're a student and you devote extra time to understanding material you learned in class by watching Khan's videos, you're already on the right track, and you're going to do well because clearly you care. If you gain some incorrect understanding of a concept because the video either omitted some fact, or got it wrong, you'll get it wrong on the test, and you'll learn why. If there's a discrepancy between one of Khan's videos and what your teacher taught you, that's a great opportunity to ask your teacher to explain it.

I don't see the downside to such a great resource.

//

Also, there are many many terrible teachers out there. I had terrible teachers at the elementary and high school level. Teachers who were either incompetent or did not care. Khan Academy is not the problem.


I find the notion that these videos are ineffective baffling. When I found these videos during my university calculus course, they literally saved my grade due to the extremely poor quality of my professor (and TAs). I find Sal to be incredibly effective, no nonsense teacher who at this point has probably taught me 5 or 6 different subjects with efficiency that no professor, nor TA has provided.

As a recent graduate: Thank You, Sal! Keep up the good work.


The critique wasn't that they are innefective, it's that they contain poor pedagogy. Their specific examples are from arithmetic videos, where the presentation and notation is inconsistent or the examples/problems were insufficient and could easily lead to misunderstanding the material. Your experience is with the calculus videos. It's possible the criticism doesn't apply to them. Or because you were a more advanced student of mathematics and were being provided feedback from your course any poor use of notation or poor problem sets wouldn't have had the same, potentially negative, impact on you.


tl;dr, with my own interpretation of the article: "although we are not students in today's world, we presume to know and understand the mind of today's student and can tell you from our own learned perspective that Khan just doesn't have what it takes to teach."

I'm certain I read nothing more than snobbery in this article. It reads like "we didn't think of this free online disruptive academy first" or "how dare you do something differently from and outside of Official Academia."

Do you know who the best teachers are? I mean the absolute best, the ones who actually get what the student is struggling with? Other students-- the ones who just got through that particular lesson, the ones that just had the exact same struggle. The students' ability to teach like this declines with experience with the material because it all starts to become second-hand and they forget all the little things they struggled with early on. When an instructor takes note of students teaching students and the hows and whys of that interaction and remembers to cover the same territory in the next class, he becomes the best non-student teacher he can.

My mother is my perfect anecdotal example of this. In her 50s, she's getting a degree. While taking calculus, she also worked in the tutoring lab. After understanding new material, she'd be an absolute godsend for students for about two weeks and then her helpfulness would fall off. (You could also attribute this to all these classes being mostly in sync with at most two weeks of lag - that being the case, she would be less exposed to the reteaching of the material ... and forget those little details.)


I think you took something different from the article than I did. They provide a critique, strongly worded at times, but not totally bashing Khan Academy or the general approach. They specify their concerns, and even offer suggestions on ways it can be improved (specifically, examining existing pedagogy and coordinating with some of the top math and science teachers to generate better content).

One of the authors is a current teacher, working with real students. He gets feedback from them either directly (by questions, comments, curses) or indirectly (homework, tests, quizzes) to gauge his effectiveness as an educator. Khan (until they added problems to the site) didn't have this feedback.

Their criticism boils down to a few main points.

1. He uses an inconsistent presentation of algebra and arithmetic work and notation, which could lead to students becoming confused when he suddenly changes it.

2. He uses a poor selection of examples, without offering more or better examples students may develop a mathematical toolset based on a flawed understanding, which will lead to problems further down the line.

3. The problems available to students are insufficient to provide proper mathematical practice and ensure that some of the common misunderstandings are shown to be wrong.


So an article on the Washington Post site based upon a for-profit founder's nit-picking of Khan's materials is representative of the right way to go about improving what Khan himself says is an effort to supplement other educational methods?

There's a difference between constructive criticism that's effectively administered vs a publicly-rendered smear attempt that tries to hide behind pedantry.


My comment was in reply to delinka's TL;DR. And you seem to be using a similar one. I don't know that it's "representative of the right way" to put criticisms like this in such a public forum, but it's not exactly new either. The first article is (is that the for-profit founder you're referring to?) definitely not constructive criticism. This article is in response to Khan's rebuttal, and at least offers a claim of more substantial research into Khan Academy's offerings before they provide their criticism.


I have looked at a few Khan videos and here is my 2 cents. The reason he/videos is effective is not because he is teaching a great content (I mean algebra is algebra). What he excels at is keeping you engaged and interested throughout. This makes tremendous difference to anyone who wants to learn. There are lot of people who know great things but can they teach it to others? Now that is an art that Khan has mastered.


Colin once again submits an article from the United States popular press, here a co-authored op-ed piece, about mathematics education reform in the United States, one of my main topics of personal research for more than a decade. The regular opinion column to which this guest piece was submitted, the "Answer Sheet" edited by Valerie Strauss, is basically propaganda for the current school system, and has been caught here on HN before stretching facts beyond all recognition to make political points.

https://news.ycombinator.com/item?id=3327847

Michael Paul Goldenberg has such a lengthy online trail of writings about mathematics education that as I entered his name in Google, autocomplete finished the search query

https://www.google.com/search?q=michael+paul+goldenberg+math...

and I was led to some of his more recent writings. (I used to interact with him quite regularly online in specialized email lists about mathematics education reform, about a decade ago.) He, um, definitely has a point of view in his approach to education reform. It's all about the providers for altogether too many people who look at education results and school practices in the United States.

The response to the usual excuses for United States school performance by another observer,

http://www.nationalreview.com/agenda/255997/are-tino-sananda...

who points out how often critiques of schools in the United States are responded to by excuses that shift blame from providers of "education" to the learners in their care:

"Consider that Americans tend to have more disposable income than citizens of other advanced market democracies, at least some of which can be devoted to supplemental instruction. After all, parents have fairly strong incentives to secure educational advantages for their children. This suggests that our schools are performing very poorly indeed.

"Don’t believe the hype."

is closer to reality than many of the critiques of outside-the-box approaches to mathematics education in the United States.

That said, I have been up-front here on HN in suggesting ways that Khan Academy can improve, for example by building more online practice that is truly problems rather than exercises (379 days ago),

http://news.ycombinator.com/item?id=2760663

"Just for friendly advice to the Khan Academy exercise developers, I'll repost my FAQ about the distinction between "exercises" and "problems" in mathematics education. It would be great to see more problems on the Khan Academy site."

and the Khan Academy developers have been listening, and I have had interesting off-forum email interaction with them as they attempt to improve the instructional model at Khan Academy.

To date, I recommend to my own children and to my clients in my own supplemental mathematics education program that they also turn to ALEKS

http://www.aleks.com/

(Yet another edit. About the time I posted this, someone else asked below another comment,

So who is making the site that will deliver more personalized instruction? Where is the research that site will use, telling all about which kinds of personalization are proven and how much effect they will have?

and ALEKS is an answer to those questions in large part. Browse around the ALEKS site to see its links to its research base.)

and to Art of Problem Solving

http://www.artofproblemsolving.com/

for more online mathematics instruction resources, and I also share specific links to specialized sites on particular topics with clients and with my children. Besides that, I fill my house with books about mathematics, and circulate other books about mathematics frequently from various local libraries.

I also recommend that all my students use the American Mathematics Competition

http://amc.maa.org/

materials and other mathematical contest materials as a reality check on how well they are learning mathematics.

In general, I think mathematics is much too important a subject to be single-sourced from any source. Especially, mathematics is much too important to be left to the United States public school system in its current condition.

I was just rereading The Teaching Gap: Best Ideas from the World's Teachers for Improving Education in the Classroom (1999) the other day. It reminded me of facts I had already learned from other sources, including living overseas for two three-year stays in east Asia.

"Readers who are parents will know that there are differences among American teachers; they might even have fought to move their child from one teacher's class into another teacher's class. Our point is that these differences, which appear so large within our culture, are dwarfed by the gap in general methods of teaching that exist across cultures. We are not talking about gaps in teachers' competence but about a gap in teaching methods." p. x

"When we watched a lesson from another country, we suddenly saw something different. Now we were struck by the similarity among the U.S. lessons and by how different they were from the other country's lesson. When we watched a Japanese lesson, for example, we noticed that the teacher presents a problem to the students without first demonstrating how to solve the problem. We realized that U.S. teachers almost never do this, and now we saw that a feature we hardly noticed before is perhaps one of the most important features of U.S. lessons--that the teacher almost always demonstrates a procedure for solving problems before assigning them to students. This is the value of cross-cultural comparisons. They allow us to detect the underlying commonalities that define particular systems of teaching, commonalities that otherwise hide in the background." p. 77

Plenty of authors, including some who should be better known and mentioned more often by the co-authors of the article Colin kindly submitted here, have had plenty of thoughtful things to say about ways in which United States mathematical education could improve.

In February 2012, Annie Keeghan wrote a blog post, "Afraid of Your Child's Math Textbook? You Should Be,"

http://open.salon.com/blog/annie_keeghan/2012/02/17/afraid_o...

in which she described the current process publishers follow in the United States to produce new mathematics textbook. Low bids for writing, rushed deadlines, and no one with a strong mathematical background reviewing the books results in school textbooks that are not useful for learning mathematics. Moreover, although all new textbook series in the United States are likely to claim that they "expose" students to the Common Core standards, they are not usually designed carefully to develop mathematical understanding according to any set of standards.

In a January 2012 lecture,

http://math.berkeley.edu/~wu/Lisbon2010_4.pdf

Professor Hung-hsi Wu of UC Berkeley points out a problem of fraction addition from the federal National Assessment of Educational Progress (NAEP) survey project. On page 39 of his presentation handout (numbered in the .PDF of his lecture notes as page 38), he shows the fraction addition problem

12/13 + 7/8

for which eighth grade students were not even required to give a numerically exact answer, but only an estimate of the correct answer to the nearest natural number from five answer choices. Even at that, very few students chose the correct answer.

Patricia Clark Kenschaft, professor of mathematics at Montclair State University in New Jersey, reported in her article "Racial Equity Requires Teaching Elementary School Teachers More Mathematics" in the Notices of the American Mathematical Society

http://www.ams.org/notices/200502/fea-kenschaft.pdf

about elementary teachers' knowledge of mathematics in New Jersey:

"The teachers are eager and able to learn. I vividly remember one summer class when I taught why the multiplication algorithm works for two-digit numbers using base ten blocks. I have no difficulty doing this with third graders, but this particular class was all elementary school teachers. At the end of the half hour, one third-grade teacher raised her hand. 'Why wasn’t I told this secret before?' she demanded. It was one of those rare speechless moments for Pat Kenschaft. In the quiet that ensued, the teacher stood up.

"'Did you know this secret before?' she asked the person nearest her. She shook her head. 'Did you know this secret before?' the inquirer persisted, walking around the class. 'Did you know this secret before?' she kept asking. Everyone shook her or his head. She whirled around and looked at me with fury in her eyes. 'Why wasn’t I taught this before? I’ve been teaching third grade for thirty years. If I had been taught this thirty years ago, I could have been such a better teacher!!!'"

A discussion of the Common Core Standards in Mathematics, "The Common Core Math StandardsAre they a step forward or backward?"

http://educationnext.org/the-common-core-math-standards/

gets into further details of how mathematicians look at the general school curriculum in the United States. It is not the worst curriculum possible, and survivors of the system often have access to outside resources to supplement school lessons, but the public school instruction in mathematics in the United States still shows plenty of room for improvement.

After edit: I was asked in a reply what I think about the essay "Lockhart's Lament." I think it is an interesting read, but less practical for reforming mathematics education than I had hoped. (I say the same in general about articles by Keith Devlin, the mathematician who popularized Lockhart's Lament.) To reform education, it is important to be relentlessly empirical, and look again and again and again at the best practices of the highest-achieving countries. That's why I prefer several of the links I submitted to Lockhart's interesting essay as policy guidance for United States parents, taxpayers, and learners.

Another edit: HN user danso just kindly posted

http://news.ycombinator.com/item?id=4301758

a link to a response by Sal Khan in the same Washington Post op-ed column about education. Direct link is

http://www.washingtonpost.com/blogs/answer-sheet/post/sal-kh...


""The teachers are eager and able to learn. I vividly remember one summer class when I taught why the multiplication algorithm works for two-digit numbers using base ten blocks. I have no difficulty doing this with third graders, but this particular class was all elementary school teachers. At the end of the half hour, one third-grade teacher raised her hand. 'Why wasn’t I told this secret before?' she demanded. It was one of those rare speechless moments for Pat Kenschaft. In the quiet that ensued, the teacher stood up." The "Secret": http://www.tech4mathed.com/MAT156/topics%20test%202/twodigit...

Since there is a strong, strong chance that many of the readers who were taught in a U.S. classroom never saw this, I have the above link included.


Thank you. I had no idea what the "secret" was myself.

What would be meant, in the original article, by the "multiplication algorithm"?

I know that's a bizarre question, but actually I don't think I could explain what that means to someone myself, so I'd better ask.


The multiplication algorithm I was taught in school was something like this:

  for each digit in the bottom number, starting with the ones digit:
    begin a new line beneath the current state.
    write a number of trailing zeroes equal to the number of digits of the bottom number you've already processed.
    for each digit in the top number, starting with the ones digit:
      write (carry + top digit * bottom digit) % 10 to the left of the leftmost digit on the bottom line of the state.
      the carry for the next digit of the top number will be (carry + top digit * bottom digit) / 10
  use the addition algorithm to compute the sum of all the numbers you wrote this way.
If you hard code it to only handle two digit numbers, it's a bit simpler. It computes the product of two numbers 10A+B, 10C+D for one digit A,B,C,D as (D * B + 10 * D * A) + 10 * (C * B + 10 * C * A). That sounds really confusing, because it is. The visual explanation relates it to something much less confusing in an obvious way.


and the Khan Academy developers have been listening, and I have had interesting off-forum email interaction

And THERE is the difference between genuinely-given constructive criticism and the questionably-motivated smearing that those folks working with the Washington Post are attempting to deliver.

Thank you very much for the links. I've already sent some of them on to my wife so that she and I can research them a bit more as instructional aids for our children.


As one of those who worked on one of the Washington Post pieces, I would invite you to come by my blog, <a href="http://christopherdanielson.wordpress.com>Overthinking My Teaching</a>, where I think you will find my motives to quite pure-better understanding of student learning of mathematics.

In fact it was very important to me that the piece I co-wrote <strong>not</strong> be a smear piece. I can't speak for the comments I did not write. But a careful read of the post itself should reveal a claim backed up by evidence. The claim is that Sal Khan is lacking some important knowledge for teaching. That's not a smear. I would gladly engage in a discussion that pointed to evidence that he does know some important things about how people learn.


I looked at your blog. From my perspective, you folks are down in the weeds. Khan isn't using the optimal technique for teaching decimals? Who cares? The problem isn't that kids aren't learning optimal methods.

The problem with education in this country is that we funnel most all of our public education dollars into a system and related organizations that are only tangentially motivated to educate our children. Watch how the public school systems and teachers unions react to vouchers and charter schools and you'll see how much they care about educating kids vs protecting their turf and power base.

I've noted that those within the education system or closely aligned with it absolutely hated "Waiting for Superman". They nitpick it and try to blow up minor faults with it in a similar way to how you're going after Khan. To those of us outside of that power structure, that documentary showed how the establishment is utterly opposed to actually solving problems in education in this country if those solutions occur outside of that establishment.

I view your articles vs Khan to be in a similar vein. What Khan has done is he's added a solution to our society for our education problems that operates outside of the current public education power structure. Rather than build on what he's done and improve on it through working with Khan or doing something better -- you folks have taken the route of trying to publicly take him down in the media.


There is a difference between being interested and doing something. All I can say is, trusting a site run by a former middle school teacher/math coach as the "savior of education" is completely stupid. Yet we have all these influential people saying such things. You would think Khan Academy would be more vocal about being a supplement and not a substitute.


I'd be interested to know (and, apologies if you've opined on it before) what you think of Lockhart's Lament.

http://www.maa.org/devlin/LockhartsLament.pdf

His seems to advocate that children should be taught to explore math problems and make discoveries rather than memorize and practice given truths. My layperson's read of your comment finds some commonality between your positions.


I used to teach math and reading Lockharts Lament was deeply satisfying. He is much closer to the light than our current system, but in retrospect I think he's got his head in the clouds a little.


It's worth recognizing that Lockhart didn't write that with the intention of producing change. It was meant as a rant.


So do you agree or disagree with the actual article?


Thank you for such a detailed response. It's particularly timely as I'm trying to figure out how to introduce my kids to mathematics.

Granted that there is a lot wrong with the current system, I'm curious what you think about the specific criticisms levelled against Khan in the OP's article. Is there any merit in the charge that he introduces the equality operator without enough explanation? Or that there ought to be more discussion in his lessons about the meaning of the decimal point?


Karl, I'm currently working fulltime on a summer project in the online education space. The differentiator is that for a given topic, there can be multiple teachers and multiple videos each trying to teach it in the best way. http://neoteach.com. I imagine you're very busy, but I'd love to hear feedback from someone who has so much education experience. And from anyone else in this thread, for that matter.


My friend works for ALEKS. I agree it's a very solid approach.


Awesome and insightful comment. Thank you.


What a beautiful post. Definitely quality.


what do you use for citation management?


From the article:

... "“I think frankly, the best way to do it is you put stuff out there and you see how people react to it; and we have exercises on our site too, so we see whether they’re able to see how they react to it anecdotally.”

Khan will put the video out there and see how people react to it. He perceives this to be a better approach than incorporating results of quality research projects into his instructional decisions. In the age of No Child Left Behind and its mandate for “scientifically based research” as the foundation for classroom instruction, this seems lazy." ...

I was agreed with the author until I read those lines. In my opinion they are disingenuous at the very least.

Every teacher, even those ones with a high knowledge on PCK, have to adapt their content every year. They try with an explanation on a topic and see how students react and based on that improve the content for the next year.

That's exactly what Khan said he is doing, publish and see how people react to those videos. It might be harder for him to measure the content in comparison with an on site teacher. But saying that "Sal Khan is on record as dismissing this research" seems an overstatement to me in the best case.


This criticism does seem to be more harsh than is necessary, but I don't see what the problem is in seeking the advice from those with more experience teaching. Khan has created something amazing, but that doesn't mean he is infallible nor that his videos should stay as they are today.

If you read the second to last paragraph, they don't suggest that Khan Academy shuts down, or that he stops teaching. They literally just say, "Hey, it'd be nice if he asked some really great teachers to look over his examples before he uses them to make sure he doesn't confuse people." I'm not an expert, but sounds like it couldn't hurt.


It's probably a good sign that Khan Academy is getting criticized by some members of mainstream media lately. It shows the growing importance of a great disruptive organization.


Or it may be just that it is worth criticizing? I personally found Khan Academy lessons of very poor quality.


I’m a huge fan of the Kahn academy videos and in order for it to get even better it needs people to criticize the curriculum so I am a big fan of this article.

I view Kahn Academy as the start to a new type of education that is in its very early stages. Kahn is a smart man who will probably take the criticism and use it to be better his instruction and add supplemental videos etc. I would be shocked if he didn’t add in a 3rd comparing decimals video after this criticism.

Keep up the great work, I know I’m watching.


"Comparing decimals. Decimal fractions (decimals for short — the numbers to the right of the decimal point) are a notoriously challenging topic in the elementary math curriculum."

Just to point out this is the most ass backwards way to talk about decimal fractions I have ever witnessed, but nothing would stop said Valerie Strauss on pedagogical insufficiency spotting... "decimals for short — the numbers to the right of the decimal point" ?!? Whisky Tango Foxtrot

Edit: downvoted is it because you would also believe decimal fractions are decimals and those are the numbers to the right of the decimal point per article explanation... because being a silent ignorant with a karma finger really fits you.


The author isn't Valerie Strauss.

"Decimals" is (in the US at least) a common way of referring to decimal fractions (that is, numbers represented like: 12.345) vs the whole number or integer representation that the students would already be familiar with (like 12) or other fractional notations like 6 7/10.


I am under the impression the author of the article is Valerie Strauss and she is presenting a small piece critique by Christopher Danielson and Michael Paul Goldenberg at the top of her article. If not, there is a problem with the placement of her name at the end of it.

As for the abbreviation presented, it is just terrible and is used in article while accusing others of lack of Pedagogical Content Knowledge.


So you believe she speaks about herself using "We" instead of "I"?

Her contribution is the first 2 paragraphs, the rest is the critique from Christopher Danielson and Michael Paul Goldenberg.

Edit: And please explain, how is the abbreviation terrible, because I've clearly missed something.


"We" may well be used instead of "I" and at the end it reads "By Valerie Strauss". The attribution is placed in a random way all through the article and that threw me.

The abbreviation is terrible because in the article it is used in reference to "the numbers to the right of the decimal point"; "decimals for short".


To the first point: The first and second paragraphs are italicized, clearly distinct from the rest. This is intended to show a distinction in voice (authorship). The content of the first two paragraphs are nothing but framing for what follows. You're either being excessively pedantic, or have elected not to read the article to have so much difficulty in recognizing authorship of the 2 parts.

To the second, I still don't see what makes that terrible. It's saying, decimals is short for decimal fractions, and provides a definition for decimal fractions.


Article starts with: "How well does Khan Academy teach? By Valerie Strauss", then "By Christopher Danielson and Michael Paul Goldenberg" on top of their contribution. At the end of the article there is a : "By Valerie Strauss". So attribution is displayed twice before text blocks and once after text blocks, if you don't see the failure in that, I am so sorry. I don't know how pedantic it is to confuse voices when they are attributed in two different ways when it is clear that the second way is the most common, but I will leave it to you to quantify it, not that I care for it. But do keep up the winding, you will be on to something, sometime soon.

Second: "Comparing decimals. Decimal fractions (decimals for short — the numbers to the right of the decimal point) are a notoriously challenging topic in the elementary math curriculum."

For the last time, decimals are NOT the numbers to the right of the decimal point like stated. "decimals" is being used for a subpar abbreviation of decimal fractions AND the left side numbers to the decimal point are a part of it, unlike what said authors state. Someone with pedagogical concerns should be awake when stating stuff like this and if you don't see the mess that is, that is your own problem. I have stated this already.


The article misses the point of Khan Academy. The point is that the world only ever has to find _one good example_ of how to teach something.

If someone comes up with a theory on a better way to teach something, cool. A/B test it and keep the winner.


Fuck that noise. If you don't like it, do it better; all this whining and nit-picking is without value. Khan Academy is innovative and game changing, but you can't innovate by insisting on perfection.


No, but after you inovation comes incremental improvement. If Khan Academy does not do this (and I have no idea weather or not they are), then another group will take their highly inovative idea and do it better.


Across the developed world libraries are closing, or being forced to reinvent themselves. They're doing this because their original purpose is being done better by new technology. It is simply no longer rational to have a big building to house information printed on slices of dead tree. Libraries and librarians do lots of important and useful things other than simply lend books, but they're having to figure out how to reinvent themselves now that the core service is obsolete.

The vast majority of contact hours in the vast majority of educational institutions consist of chalk-and-talk - someone writing things on a board and talking. The available evidence shows that there is no clear benefit to doing this in the flesh over delivering the same approach through video, and that there might be significant benefits to providing it in a modular format that can be paused and rewound. Sal might not be the greatest math teacher on earth, but soon enough, somewhere on the internet will be lessons by 99th percentile teachers on every imaginable topic.

If your best argument is "We can do what the internet does, only marginally better", then you're in deep trouble - we've seen how well that has played out for any number of people. The economies of scale are too great, the rate of iteration too rapid. You're just not going to beat the internet at supplying data. Educators and schools have to work out what they are uniquely equipped to do, or face the same inevitable obsolescence that is befalling libraries and travel agents and local newspapers and record stores and myriad other businesses.


It should be noted that Kaplan, Inc. is owned by the Washington Post Co. and is, I believe, the WaPo Co.'s largest source of revenue: http://en.wikipedia.org/wiki/Kaplan,_Inc.

(I'm of the belief that it's possible for a large news company to give equal commentary share to competing interests, but I don't follow the WaPo's education coverage enough to be able to make a judgment in this case)


It seems to me that most of the unpleasantness in Khan Academy criticisms stem from the fact that, most of these comment concern other peoples' comments on Khan Academy. Revolutionary/Messiah v/s borg/wrath-of-khan/emperor-without-clothes and so on.

This is sad because the actual message, which is valid in some instances and informative in all instances, gets lost in the noise. This is more so, given that people at Khan Academy are responding positively to specific concerns on specific topics.

And unlike for-profit companies, all his work, from the most boring video to the best, are available to be criticized. We only see a few clippings from, most likely, the very best videos from for-profit companies.

I hope the real critics and the real skeptics, i.e., those who would like to make Khan Academy a success, will continue to bring their specific concerns to the table; and just not all the distracting noise.

(Now, it is strange that the authors while pointing out the exaggerated praise for Khan Academy, fail to point out the abuse that Khan had to endure. Even stranger is that some commentators dismiss the abuse as "satire".)


Where is the video that represents the "right" way of comparing decimals? I'd be genuinely curious to compare it with the khan video. And if that ever happens, then Khan Academy is a net win in my opinion.

I would think it would be easy for the "nit-picking experts" to produce that and it probably would have taken less time than the formal analysis they did. Probably cheaper too.

edit: wording


Any critique that world-class teachers give Khan Academy would apply to most K-12 math teachers as well. I think people are worried because Khan Academy can spread much further (and do much more damage) than a conventional teacher, who is fired if standardized testing scores drop below an arbitrary amount.

BUT the same effect is seen on Wikipedia, which has been reviewed and corrected more than thousands of other encyclopedias, simply because it's so open and accessible. Khan Academy was originally run by one guy, but they're starting to open up and partner with other educational entities. They aren't going to go unchecked. By no means is Khan Academy hurting the education system, unless you look at things from an economic or political standpoint, in which case it's potentially disruptive. But that would be cruel, wouldn't it?


"Our view is that content knowledge alone is inadequate for quality instruction."

I cannot disagree more. The best teachers I had were college professors who were all experts in their field and never took a class on pedagogy or education. But they had the autonomy to change their teaching style based on what was most effective for them and their students.

Our grade school teachers would be a lot better if they were experts in their domain of knowledge and given more leeway to teach according to their strengths and their students' needs. As it is, public school teachers are pretty much automatons whose actions are dictated down to the minute by school boards.


My best teachers were also content experts.

My worst teachers by a long shot were also content experts, holding, in one case, the research chair of an academic department in a renowned research university.

Couldn't teach to save his life and was lucky that the tutors put in a lot of extra hours so that around 50% of the enrolled students passed his fairly easy course (it was a revelation that after I had failed, and had to re-sit during the summer, I asked an academic in a related field to coach me based on a text, and his explanations were lucid, to the point, had an expository style that engaged and that he actually wanted to address the material at hand).

An intelligent person with some domain knowledge, good teaching materials and firm grasp on how students learn beats someone with all the domain knowledge in the world who is a hopeless teacher, in my experience.


It's kind of an interesting question. Is it better to educate masses with an inferior product that breeds misconception, or fewer people with a better product that limits misconception?


If it breeds misconception, can you really call it education?


Perhaps the word "breeds" is strong. I would argue that even though Khan's lessons are very imperfect, the accessibility offered may be a worthy trade-off.

If knowing math at a superficial level opens doors for other learning, it's hard to argue that it's NOT a worthy trade-off.

We as math teachers strive for perfection, but the truth is that having a deep understanding of what an equals sign is and how it should function isn't important for most people in their lives. Sure those in math careers will want that depth (and they'll get it, since Khan alone can't prepare them for that career), but everyone else will be fine whether they use the equals sign properly or not.

In a lot of ways it's like prescriptive vs. descriptive linguistics. Are we going to be the equivalent of a grammar nazi and come down hard on everyone we see that uses improper notation? Or can we be satisfied if there is some understanding there, even if it's imperfect or communicated poorly?


One snob article vs. a huge body of innovative work.

Game, set, match to Mr. Khan.


The thing I find most bizarre about Khan Academy (which, in principal, I love) is the whacky focus on Khan. Why not crowd source the tutorials?

In my opinion Stack Overflow is a better model for this stuff. Imagine something like Stack Overflow focused on video tutorials covering concepts that got up voted. (heck, maybe it exists.) why can't I upload my take on "slope" (or whatever) rather than just post Q&A on Khan's?


Can anyone weigh in on their differing arguments regarding the definition of slope? I am not a maths expert by any means, but am genuinely curious who is correct here. Or is this a matter of one being technically correct versus the other being correct in practice?


Khan Academy is social-network type of learning, where you learn from the community. This is good. But learning from expert educators is also essential and perhaps irreplaceable. There are a lot of short-sighted people, who are marveled by current technologies that allow people interact remotely and immediately jump to the conclusion that we have an answer to learning, while dismissing the entire tradition, culture and knowledge of and about learning that has been established for centuries. Now, if Khan wants to make a quick buck, that's fine. But he's serious about teaching and learning, he should realize that Khan Academy and its approach is only complementary (at extremely great at that) and is not a replacement of the traditional ways of teaching and learning.


Wow, such a high quality discussion on HN especially compared to the one under the article. And on a topic that's only tangentially related to startups and tech...


So because its not perfect, lets drag it through the mud.

This is ONE MAN.


170,000,000 lessons.

"We contend that"

No. You cannot contend against 170 million.




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