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Why Sal Khan't: On Learning by Making but Teaching by Telling

punyamishra.com

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Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#52
From what I know of the Khan approach, it's akin to "flipping the classroom" [0], which has gained pretty wide acceptance. It was pioneered by Harvard physics professor Eric Mazur.

(I use the flipped classroom approach extensively. But the legal profession being the eager embracers of novelty that we are , I refer to the approach as "enhanced Socratic method," given that Socratic method was something we all endured in law school.)

For math and engineering courses, the basic flipped-classroom approach was used at West Point for over 150 years: In the so-called Thayer method, students study textbooks in advance, then in class, they work on problems on chalkboards. The instructor moves from chalkboard to chalkboard, coaching the students in real time. [1]

(I do much the same thing in my contract-drafting classes: In small groups, students do drafting exercises using online whiteboards. I lurk on my laptop, quietly coaching in person as needed.)

[0] https://bokcenter.harvard.edu/flipped-classrooms

[1] https://flippedlearning.org/syndicated/avoiding-flipped-lear...

Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#53

Is the article about something else than how math on Khan Academy was thaught? I remember minimal videos (3-13 min, usually 5-8), and then exercises drilling the techniques until you understand it and don't make mistakes. If you got a perfect score (no mistakes whatsoever), you went a little faster. That's learning by doing, or am I wrong? Or are there no exercises for things other than math?

I agree with you. It's just an attention bite as nobody would care about this article if it wasn't focused on something as big and popular as Khan Academy. It's clear that the author has never used it as a place to learn something.

Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#54

Is the article about something else than how math on Khan Academy was thaught? I remember minimal videos (3-13 min, usually 5-8), and then exercises drilling the techniques until you understand it and don't make mistakes. If you got a perfect score (no mistakes whatsoever), you went a little faster. That's learning by doing, or am I wrong? Or are there no exercises for things other than math?

Sounds like you should read the article if you have questions about what the article is about?

This article is an example of a rather poor piece of writing. You can't blame people for skimming through it.

Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#55
post #23

Earlier quoted context omitted.

There's a difference between pacing (good), and repetitive speech (bad). Between pacing and repetitive speech.

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.

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.

Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#56

Earlier quoted context omitted.

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.

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…

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.

Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#57
post #4

Earlier quoted context omitted.

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.

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…

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.

Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#58
post #3

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…

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.

Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#59
post #4
post #3

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…

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.

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.

Re: Why Sal Khan't: On Learning by Making but Teaching by Telling

#60
post #14

Earlier quoted context omitted.

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…

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 dra…

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.

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