8/23/2026 at 5:08:04 PM
Overall, I do agree with the thesis but:> Now… how does Sal Khan want my kid to learn?
> Watch a video.
I find this a little uncharitable. I learned a lot of math at a young age from Sal Khan's early videos (back when he used to erase by switching to a black pen and scribbling across the entire screen) and, to put it in the author's terms, it served as an easy-to-digest scaffolding on top of which to build a deeper understanding. I don't think Khanacademy ever sold itself as a magic learning resource that removes the need to work out problems yourself.
by skulk
8/23/2026 at 8:38:11 PM
The attacks on Khan here personally irked me.I grew up in a small rural town where math teachers were rare and good ones were nonexistent. I still remember watching Sal Khan's videos on calculus after struggling to get any grip on it from my frustratingly uninterested teacher who was forced into the position after our actual teacher retired. After I saw them I came back with a fire in me because for the first time he exposed me to the beauty of calculus.
This guy is completely wrong about Khan not inspiring students to care. Sometimes all students need is to see what caring looks like to ignite it in themselves. You can feel how much he cares just by watching him because the video is the product of all that caring, and he does it for millions of people.
But thank you to this blog author for being brave enough to call out Khan's failures, I am sure it'll help education much more than Khan did.
by mindwok
8/24/2026 at 2:02:25 PM
> "Sometimes all students need is to see what caring looks like to ignite it in themselves."Excellent point, well expressed.
(Also, IMHO the sarcasm in your final sentence detracts from your comment.)
by chrisweekly
8/24/2026 at 7:11:22 AM
> The attacks on Khan here personally irked me.No good deed goes unpunished.
by scotty79
8/23/2026 at 11:17:45 PM
I don't have a problem with Khan's site existing, but it's disappointing that often answers to requests for learning materials/ideas begin and end with Khan Academy. My personal opinion is that Khan's videos are roughly comparable to an average-quality classroom teacher lecturing about a typical mediocre curriculum.They have some significant advantages compared to (just) a classroom: (1) They set a quality floor – sometimes a teacher can be really incomprehensible, or mean, or whatever, but Khan's videos are consistently okay. (2) They are available from anywhere, without need for special social/technical infrastructure, like enrollment in school or access to a university library. (3) They are self paced, which means they can better accommodate the various interest level, motivation, and speed of different students. (A typical classroom also has some advantages: it gives social setting, a consistent schedule/structure, and human feedback.)
I'm also disappointed though, because it seems like, given production resources, there would be potential to make widely available materials that were much better than average lectures. With significant production effort (a team of subject experts and content creators doing a lot of dedicated work on each topic) I think it would be possible to make something truly great, but Khan's videos fall so far short of my imagination. For any particular topic, there are typically other freely available resources which I think are better.
I've also been disappointed because many people have hyped the site as being extraordinarily amazing, but when I have looked at it, what is there doesn't match the hype.
by jacobolus
8/24/2026 at 1:11:10 AM
>I don't have a problem with Khan's site existing, but it's disappointing that often answers to requests for learning materials/ideas begin and end with Khan Academy. My personal opinion is that Khan's videos are roughly comparable to an average-quality classroom teacher lecturing about a typical mediocre curriculum.Its better than average quality classroom teacher in my experience.
And the point is this didn’t exist online at the time. His resources were strictly more. I imagine its still hard to find a single free resource that matches its breadth and quality.
by nonethewiser
8/24/2026 at 1:18:05 AM
> materials that were much betterDo you have few examples?
by blackoil
8/24/2026 at 1:38:51 AM
Personally I like books, but there are also many, many lecture videos on YouTube, some of them excellent (though I think they could still be better with bigger production teams and higher budgets). For college-level technical subjects, there are also e.g. many MIT lectures on OCW. If you have a specific topic in mind, I urge you to search around. (Making a long list of my own book/website/video recommendations about various topics here seems a bit off topic and out of scope.)by jacobolus
8/24/2026 at 10:28:36 AM
> For college-level technical subjects, there are also e.g. many MIT lectures on OCW.There are? I know an OCW course includes "lecture notes" pdfs. Does it have the lectures too?
For example, the course "distributed systems" is available on OCW as 6.824, from spring 2006: https://ocw.mit.edu/courses/6-824-distributed-computer-syste...
MIT has renumbered the course, but it's still around: https://pdos.csail.mit.edu/6.824/ . Don't be fooled by the URL; it's now 6.5840.
And a series of lectures is available too: https://www.youtube.com/@6.824/videos . They're from spring 2020. They link to the course website for spring 2020, which is great. But it doesn't link to them, and OCW doesn't know about any of this, as far as I can tell. The 6.824 lecture series is pretty hard to discover, too, because it's uploaded by an account dedicated solely to that one course, which isn't related to any other MIT lecture videos.
by thaumasiotes
8/24/2026 at 7:50:10 PM
Some OCW courses have lecture videos, while others do not.by jacobolus
8/24/2026 at 10:59:26 PM
Is 6.824 one that does, or one that doesn't?by thaumasiotes
8/25/2026 at 2:41:28 AM
From your OCW link, you can see the Spring 2006 version of the course has syllabus, lecture notes, readings, lab assignments, and 2 quizzes available, but no videos. Separately, videos of the 2020 version of the course are on YouTube: https://www.youtube.com/playlist?list=PLrw6a1wE39_tb2fErI4-W...by jacobolus
8/23/2026 at 7:19:28 PM
Yes, exactly. I have also learned a lot of math, grammar, science, and other subjects from Sal. In most videos, Sal explicitly states to pause the video and try out the problem before he works through it. I do think that KA's style of teaching needs some getting used to (this was never a problem for me as it was one of my first teaching platforms). However, once you get used to it, it is a wonderful experience.by sudo_cowsay
8/23/2026 at 7:55:56 PM
Khan Academy is a treasure, and is how I re-learned math in my 20s after not taking it seriously in school. Then moved on to MitX for science [re]fam.I am having my kids learn math with Kahn academy if we don't have anything better by that point.
by the__alchemist
8/23/2026 at 5:42:30 PM
I don't agree and the hype surrounding his efforts was something much greater than what KahnAcademy actually is (a very useful resource).He sold his vision in "The One World Schoolhouse" which was essentially global learning via all the best videos (and one unified curriculum) you can make and teachers effectively being technicians/teaching assistants. It was the vision that utopian minded technologists craved in the early aughts.
by fullshark
8/23/2026 at 6:18:58 PM
It's not a bad idea in concept, but the core problem is what he delivered was:"essentially global learning via all the Khan videos, in math, by him, and in other subjects, by his team."
Khan Academy is 2010-era state-of-the-art for rote learning and procedural knowledge. That's a helpful resource, but as one world schoolhouse, there is:
- No room for creativity, or much of anything similar from students (outside of the fantastic JavaScript projects).
- No room for outside innovation.
- A personality cult. Any ideas MUST be attributed to Khan.
by blagie
8/23/2026 at 6:54:14 PM
Creativity isn't learning, it's the application of learning, and that's not what school is for. There has always been value in somebody showing you how to apply a math technique and practicing using it to solve problems. It's not creative but it gives us the skills to do useful things in the world - including creative things. Even pure rote learning (such as reciting the periodic table) is useful so you can later draw on that knowledge without interrupting your attention on the higher level thinking (such as creativity!) that you're doing.by foxglacier
8/23/2026 at 8:42:48 PM
I don't want to tangle myself in a "technically correct" kind of discussion however I'd like to point out that Bloom's taxonomy - a widely used model in pedagogical context - has a level for creative work.It is the highest level of learning, but still a level of learning.
by john_fushi
8/23/2026 at 10:43:20 PM
> There has always been value in somebody showing you how to apply a math technique and practicing using it to solve problems.Only if your goal is to teach people how to solve that particular problem. But it’s not the best way to teach mathematics.
For my money, the best way is problem based. I heard of one math teacher who had a video playing as the students walked in. The video was a weirdly shaped bucket being slowly filled by a hose. Students came in, saw him sitting up the back, got fidgety then someone asked “how long will this take??”. At that, he shot up and said “good question”! And they spent the rest of the class trying to estimate how long it would take for the bucket to be filled. Complete with diversions into flow rate, volume, and so on. He made the students ask the question. Then got the students to try and answer it themselves, helping them work through their own ideas on the board.
That’s beautiful teaching.
by josephg
8/24/2026 at 4:03:19 AM
> that's not what school is forMost people would disagree with you about the purpose of school.
Article cites Dewey, who wrote a lot of text about what school is for. Friere is also worth reading there. You'll see a diversity of perspectives.
by blagie
8/23/2026 at 5:20:07 PM
Side note, but much as I like Khan Academy overall, I've always struggled with Sal's slow and repetitive speaking style in the videos."Now you add the five ... [pause] ... add the five ... add the five to the seven ... to the seven..."
Running them at 1.5 - 2x helps a bit, but it's still annoying to the point that I find it very distracting.
by jbstack
8/23/2026 at 7:23:56 PM
While it depends entirely on personal opinion, I believe that it helps significantly. It helps build up the problem/solution from the ground up and he goes through each step out loud to help a student understand. I get that some people hate it and think it is so childish for such simple steps. For other people, it helps a lot. Learning on KA works best if started aat a young age and done consistently (you get used to the style and you learn everything from the ground up).by sudo_cowsay
8/23/2026 at 8:35:39 PM
In my case, it's not so much that I find it childish, it's that I find it incredibly distracting which means I can't focus as easily on the content. Instead of "oh, now I understand how that equation works" I catch myself thinking "why is he repeating the same word over and over - that's so annoying!". Then my brain starts obsessing over "when is he going to do it again?", even though I don't want it to. It's a bit like trying to deliberately ignore something. It becomes all you can think about.by jbstack
8/23/2026 at 11:29:59 PM
Oh ok, got you. While it entirely differs on how different people receive ideas, for me, I just try to keep the end goal in mind (what are we ultimately moving towards) and just think of those repeated words as just small steps rather than just annoying repeating word.by sudo_cowsay
8/23/2026 at 10:10:13 PM
YMMV but I found the style very helpfulby only-one1701
8/23/2026 at 5:36:45 PM
OTOH creating neural connections takes time. It's a real distance. Small for us, but great for the cells. That's why explaining difficult concepts too fast, while cool for people getting things instantly, is not good for general population.by wafflemaker
8/23/2026 at 7:20:30 PM
I very much agree and it saddens me often when I see folks dial it up to 1.5x or 2x "because it is boring otherwise". They might think they just get as much, only in half the time, but I'd hypothesize that they retain less because the mind needs some time to digest.Similar with the trend to auto-cut pauses that speakers make, just to cram in more text into a youtube video. Destroys not just the pacing but any chance for the mind to take its time.
I'd love to see studies about this.
by teiferer
8/24/2026 at 4:25:10 AM
There’s a great lecture on giving lectures by an MIT prof. He says you can give no more than 3 ideas per hour, and you must repeat yourself at least 3 times for each idea. And while, part of his thesis is because people might miss something due to their attention, and needs of the group vs individual I think his experience is still highly relevant. I know that I don’t learn as much unless there’s room for almost boredom. I find there is a feeling similar to boredom that I have to experience to really internalize something. It’s almost like I can feel the neurons rewiring (though I suspect it might just be an emotion that encourages the energy expenditure necessary for learning). If I skim, or do doubletime, then that feeling usually never comes, and there’s a good chance my future recall will be poor…by milesvp
8/23/2026 at 10:30:53 PM
When I’m understimulated by a teacher, my mind wanders. I’ll start thinking about something else entirely. When my mind comes back, I’ll have missed a couple minutes of content. I can overcome this with willpower, but doing so is exhausting.Playing videos at 1.5-2x fixes the problem entirely. My attention is held without any effort.
If a concept is new or difficult enough, I just slow the video back down or pause it whenever I need to think things through.
by josephg
8/24/2026 at 3:22:00 PM
> When I’m understimulated by a teacher, my mind wanders.A good solution to this is to train focus. By giving in to the dopanine craving you are depriving your mind of the space it needs to process.
by teiferer
8/24/2026 at 3:39:25 AM
I'd argue (as the article does), that you don't 'really' learn from watching stuff, fast or slow, but from actually working with and doing. This is completely obvious in the physical domain. You could take a ten year course on the basketball free throw and watch a billion hours of video on it, but then when you get on the court and actually do it - you're going to shoot pretty much like somebody who's never shot before.And I think the same is true in academic domains. If you're trying to think about something consciously, you're going to do a poor job of it. And the only way to get the unconscious competence is through a bunch of 'doing'. Chess is a great example of this because it's purely mental yet again you're never going to gain any degree of significant competence without playing a lot. Interestingly this even applies after mastery. A master who has played e.g. 1. e4 their entire life and then swaps to 1. d4 isn't going to be playing at the same level as he plays 1. e4 even if watches thousands of hours of videos on it beforehand. That connection you make by doing and interacting with things is just critical.
by somenameforme
8/24/2026 at 3:27:32 PM
Indeed, well put.It is a spectrum. If you give your mind some space, it will start churning through the key ideas, fill in gaps, turn things upside down, ask questions. That starts during the explanations and their pauses. And ideally you have some empty time right after to think about it, maybe do an exercise, maybe try to explain it to somebody. Work it, like a good dough.
2x listening suffocates this process. Like too little sugar or too low temperature or too little rest for your yeast dough. It might "feel" good but you are missing out so much...
by teiferer
8/23/2026 at 8:34:26 PM
I don't think you can make blanket statements. Consider:1. Teacher 1 speaks at 100 words per minute.
2. Teacher 2 speaks at 50 words per minute, for the exact same content as Teacher 1.
You're not really losing anything by playing Teacher 1 at normal speed vs Teacher 2 at 2x speed. For every learner, there will be an optimal teaching speed for a given topic. This may mean listening to some audio at normal speed, some at higher speeds, and some even at slower speeds. I always customise my playback speed to the specific content I'm trying to learn.
by jbstack
8/24/2026 at 3:30:24 PM
Those two teachers will rarely say the same words. Chances are, teacher 2 chooses their words more carefully, and gives you then space to absorb that higher information density. In the end, both may communicate the same amount of information.by teiferer
8/23/2026 at 8:43:14 PM
It's not about the rate of speaking but rather about what is actually being spoken. I am currently going through the Neetcode DSA course and it's just obnoxious. His video on Union Find, a 15 LoC algorithm, is 20 minutes.by dprkh
8/24/2026 at 5:17:11 AM
I think there was a study omparing watching an educational video in 1x speed and watching it two times back to back in 2x speed equating the time spent on the material, which found the second group faired better.by mahdi7d1
8/24/2026 at 3:33:25 PM
Interesting, I'd like to read that study.Though it's not the question I asked. Would the second group fair somewhere close to the first if it only had listened once?
(I don't buy the argument that this would not be fair since they would use the extea time to watch more stuff ... because that's rarely what people do with their extra time. Especially not watching the same thing again.)
by teiferer
8/24/2026 at 3:12:36 AM
I remember reading a study a while back about learning from videos at 1.5x to 2x speed. The key observation that actually made the learning more efficacious was to watch the video at 2x speed two times back to back. Apparently, this method was also better than watching the video one time at normal speed. I suppose it's because one get twice the exposure for the same amount of time.I haven't looked for the study, but I can if you are truly curious.
by hirvi74
8/23/2026 at 7:08:10 PM
There's a difference between pacing (good), and repetitive speech (bad). Between pacing and repetitive speech.by jbstack
8/23/2026 at 7:22:47 PM
Ironically, spaced repetition is the key to successful learning.Obviously one can overdo it. And there is variance in what people require. But not giving things time, instead giving in to the dopamine-craving, that's killing your learning abilities.
by teiferer
8/23/2026 at 8:30:31 PM
Repeating a sentence twice in a row during an explanation, is not spaced repetition at all. Spaced repetition means testing recall at increasing intervals, usually starting 1 day apart."Paris is the capital of France. Paris is the capital of France" -> not spaced repetition.
"Paris is the capital of France. [one day later]. What is the capital of France? [three days later] What is the capital of France?" -> spaced repetition.
And in fact, it's this plus practice where the real value lies in learning and memorising. The only purpose of an explanation from a teacher is to help you understand the concept. Generally once you understand it once, you don't need to understand it again - unless you forget, and that's where the practice / spaced repetition comes in. That's why I prefer the teaching part to be as efficient as possible, so I can focus my limited time on the parts that will make me internalise it.
by jbstack
8/23/2026 at 6:16:13 PM
I originally learned linear algebra from Gilbert Strang's OCW videos, and I was only able to stick with them by 2x'ing the playback rate; at this point, hearing Strang at his normal speaking rate sounds to me like hearing him after a Robitussin bender.by tptacek
8/23/2026 at 10:33:47 PM
I wish YouTube let you increase the speed of videos past 2x. I play almost everything at 2x now, and I have no problem comprehending videos at that speed. I’d like to try 2.5x or 3x but the ui doesn’t have that option.by josephg
8/23/2026 at 10:59:30 PM
There's a bunch of different chrome extensions that do this, and you can do it yourself from the Chrome console with `$0.playbackRate = 3` or whatever.by tptacek
8/24/2026 at 3:50:05 PM
I think youtube premium lets you hit up to 4xby sylos
8/24/2026 at 1:21:56 AM
You can do it in YT premium.by blackoil
8/24/2026 at 4:37:21 AM
Weird thing to put behind a paywall! I'll try some extensions.by josephg
8/24/2026 at 2:49:51 AM
[dead]by quitting33
8/23/2026 at 8:42:21 PM
It might be annoying if you already know the content. Frame it for the least common denominator (pun intended) - the person who has the time and needs the repetition to pick up a concept.by turtlebits
8/24/2026 at 6:30:34 AM
Not sure that I'm adding anything to this, or that what I'm saying is even relevant, but Sal does (or did) have a deviated septum, and as someone who suffers from the same / similar root cause of breathing issues, I'm pretty sure speaking is (or was) taxing for him, probably contributing at least mildly to such a style.Personally I like it.
by barrenko
8/23/2026 at 6:47:10 PM
This is exactly what my kid said about why he doesn’t like Kahn academy.by homieg33
8/23/2026 at 7:01:55 PM
What would you recommend over khan academy?by dprkh
8/23/2026 at 7:15:37 PM
I've not tried it myself, but I consistently hear good things about Math Academy. It uses a knowledge graph so that it knows whether you've satisfied prerequisites for a topic, and it adapts itself to your level. I've never taken the plunge because it's very expensive at $49 a month, but it seems to be the one that serious maths learners use.I did the trial of Brilliant the other day. You can get 7 days free, then another 7 days added if you cancel the first trial before the end. After that you can continue to get 2 free lessons per day with ads. I think it's about $20 a month for unlimited lessons. The maths problems are more visual (which makes them quite intuitive) and it has a nicer, more polished UI than Khan Academy. It's easier to stay in the mood for doing more lessons. The main downsides compared to Khan are that the explanations are quite minimal (short descriptions, no videos), and it doesn't reach as advanced a level as Khan. I'm looking at it as more a way to do a refresher on the maths I already learned at school rather than a serious learning tool. If it were $5 a month I'd probably consider subbing for a couple of months and trying to blitz through all the material before switching back to Khan to fill in the gaps.
by jbstack
8/24/2026 at 2:50:44 AM
Herbert Gross' lecture style, in MIT Calculus Revisited, would be nice:https://www.youtube.com/playlist?list=PL3B08AE665AB9002A
by rustcleaner
8/23/2026 at 7:25:36 PM
While I am a strong supporter of KA, I just use regular schooling to review and back up what I learned on Khan.by sudo_cowsay
8/23/2026 at 6:41:48 PM
The article is indeed uncharitable. Nowhere does the article mention the fact that there are exercises AND that you can explore the website and the different resources in the way you like. You don't even need to watch videos if you don't want to.You also do not need to linearly follow the topics/videos. You can take a few quizzes from some topic, notice you don't understand something completely yet and instead pick up more trigonometry instead.
I've worked through Khan academy in a way similar to what the author describes as a good flow, but then all within the Khan Academy platform. The platform even allows for discussions and questions.
To me the problem is much more that motivation or a destination is not something that Khan Academy will give you. Then again, so won't most teachers. I much preferred Khan Academy over most of my math teachers, but occasionally I've had teachers who helped me love a subject I barely knew beforehand.
by Nebasuke
8/24/2026 at 11:26:27 AM
I think it is okay.I have benefited a good deal from Khan Academy, and was quite disappointing to go back and see that they seem even more focused on showing videos than they did 10 years ago.
by wodenokoto
8/23/2026 at 5:21:08 PM
My understanding is that the idea behind Khanacademy is to switch the classroom -- learn a topic as homework; do the questions in the classroom. That way the teacher can assess (and help) the students.The other idea is that a student only advances to the next topic once they've mastered the current topic (e.g. by getting 4/5 questions right). The theory behind this is that if you don't understand a concept/topic then it is harder to understand topics that depend on that.
This does mean that students will be at different topics/stages. But because of the structure of the teaching a teacher isn't moving on to a new topic leaving students to fall further and further behind.
by rhdunn
8/23/2026 at 7:12:17 PM
The idea of Mastery Learning seems to resurface every couple decades. I guess because it pretty appealing but requires more per-student customization; there’s always a hope that now, finally, we’ve got the tech to let everyone advance at their own pace.IDK. Maybe some sort of RAG-on-textbook solution will let us do it.
by bee_rider
8/23/2026 at 6:05:22 PM
The idea is for the students to watch the videos outside of class and this frees up time for the teachers to provide individual help.by UltraSane