Month: August 2012

Total 11 Posts

Khan Academy’s Introduction to Programming Modules Are Really Something Special

Khan Academy released their Introduction to Programming modules today and they’re really great. Go play. Here are my favorite pieces:

Changes to the code affect the output dynamically. No rendering, no compiling, no reloading. Change the width parameter of a rectangle in the code and the rectangle changes without any extra effort on your part. You can hover your mouse over any parameter and a slider appears, letting you change that parameter smoothly over a range of values. (Bret Victor modeled this kind of programming environment in his Inventing on Principle talk. Try it out on the tree generator.)

Contrast this with Codeacademy where you have to click “Run” or press “Enter” to see the result of your work. Or just now, when I was working on my front-end web development final project, I would make a change to my code in one window, click over to my web browser in another, and then click “Reload” to see the result. That friction may not sound like much but it often makes programming feel less creative and more mechanical.

You can interrupt the lectures at any point and mess around with the lecturer’s code. You press play on the video and you watch the lecturer type code on the screen. You hear the lecturer talk about the code as she types it. This is how I’d predict “Khan Academy does introduction to programming” would look. But the student can press pause at any point, mess around with the current state of the lecturer’s code, and watch the result change in the output window. She presses play and her changes revert back to the lecturer’s code and the lecturer continues on.

Don’t underestimate this feature. This means that if an explanation is unclear, if the student doesn’t understand the effect of a given parameter in a function, she can pause the explanation and instantly generate a series of examples of the parameter’s effect. (eg. “Oh I thought that parameter was the top coordinate of the rectangle but now I see it’s the height.”)

The lecturer is Vi Hart Khan Academy intern Jessica Liu. That’s (still) fun.

Students are doing and listening simultaneously. This isn’t the place to contrast Khan Academy’s treatment of math against its treatment of programming. Let’s just note that students play a very active role in these lectures. They’re going to love it.

2012 Aug 14: John Resig has an interesting write-up of the development process and explicitly namechecks Bret Victor’s talk as an inspiration.

Featured Comments:

The Puzzle School:

If we can add in challenges (e.g. Angry Birds) where students have access to environments and tools that offer this type of instantaneous feedback so that students can solve those challenges through hypothesis that can quickly be validated or invalidated through the feedback loop then I think we will have a learning environment that completes the loop by providing intrinsic motivation to engage with the environment by solving the challenges.

Michael Pershan:

I love that the lectures are from a woman, that she uses “her,” “his,” “he,” and “she” in roughly equal proportion and talks about “your mother, the programmer.”

Matt McCrea:

Wouldn’t it be great if the math section were executed in a similar way? Imagine a video that poses a question with a scratch space to execute and test solutions. Obviously much more complicated, but I’d bet there are certain situations in which at least it’d be a great step in the right direction without too much effort.

David Patterson:

I think most Computer Scientists would cringe at this being called “Computer Science.”

Khan Academy Does Angry Birds

In case you missed it, Justin Reich and I are co-sponsoring the #mtt2k prize and the eligibility window for applications closes August 15. Upload some commentary on a Khan Academy video to YouTube and tag it #mtt2k. You could win a few hundred dollars to take the missus or the mister to the boardwalk before school starts.

Here is my submission, playing out of competition.

If you couldn’t make it through the setup (a Khan-style explanation of Angry Birds) here is the punchline:

Okay, wait. Obviously, Khan Academy would never lecture about Angry Birds. But what makes Angry Birds different from math and science? Angry Birds makes it easy to play, experiment, get feedback, and learn. I’m not saying lectures and explanations are never necessary in math and science — or in Angry Birds, for that matter. When I couldn’t get past that one really tricky level, I went online and found a walkthrough. But the walkthrough — the explanation — wasn’t the first thing I did when I experienced Angry Birds. So why does Khan Academy make an explanation the very first thing a student experiences with a new topic in math. When we put the explanation first, we get lousy learning and bored students.

Comments open until I come to my senses.

17 hours later. Comments closed. I couldn’t handle it. Sorry.

“The Verb Of My Life Is Learning”

Comedian Louis CK, on bypassing ticket retailers to sell seats directly to fans through his website:

Well, it’s all so interesting. It’s all so interesting. It really is. I love knowing why I was able to sell out in one town, and why I wasn’t in another town. I love knowing what goes into everything—the economics, the technical aspect, and how to create the ideas in the show. It’s great. If you can have access to all of that, why would you not want to know? I just love learning. I think learning is how you live. The verb of my life is learning.

There are people who find failure interesting. Those people’s failures are often more interesting than their peers’ successes. Their lives also tend towards success even though the prospect of a successful life motivates them less than the prospect of an interesting one.

The Math Edublogosphere’s Welcome Mat

Sam Shah, chalking up another reason to love the math edublogosphere:

For a few weeks now, I have had this idea bouncing around in my head. A new blogger initiation! All it involves is writing four blogposts. There will be no hazing of any kind, except for the kind where we all say how much we think you’re awesome. That’s a form of hazing, right? Like happy hazing?

It’s a great idea and I can’t wait to read the summaries. If you haven’t created your own faculty lounge online, now is the time. Sign up by August 14.

[LOA] Misconceptions

Bryan Meyer claims to prefer the abstract task on the left to the concrete task on the right:

But both of those images have information that is extraneous to the question Bryan poses about them. Color information is irrelevant in both, for instance, so you get rid of it. You don’t need the names of California’s missions or the name of the ocean to its west. Both images are in need of abstraction. Therefore they are both concrete.

Or at least they’re more concrete than what we get after we ask ourselves:

  1. What information is important?
  2. How do I represent it?

This points to the highly subjective nature of the adjectives “abstract” and “concrete.” They’re often statements of preference (eg. “I prefer concrete to abstract” or vice versa) and they’re both relative terms. Everything is more abstract and more concrete than something else on the same ladder. But we’re looking at two different ladders here, not one.