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Mathematicians are hoarding a type of Japanese chalk (2015)

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Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#91

Post by jordigh »

dwater wrote: post #41
LeifCarrotson wrote: post #31

Hands-down, the best presentation and note-taking math class I recall in college (discrete mathematics, a graph theory course, heavy on drawings) was run through a Wacom pen display on the lectern, linked to a projector. The professor could accurately and cleanly draw the required notation with his hand flat. Why erase when space is infinite, just scroll and/or zoom in the desired direction. A full color spectrum was…

That sounds similar to the approach my Prealgebra teacher used in 1994. She had an overhead projector with a roll of plastic transparency sheet attached. She wrote across the bottom of the projector and then rolled it up as she went along. Different color pens were available. You could follow along and understand the process, and there was plenty of time to take notes as the material rolled up the screen.

Huh, this sounds almost exactly like my experience too, down to the same year and subject! This was in Mexico, but our teacher was from the southern US, I believe. I wonder if it was a particularly popular teaching method of that year.

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#92

Post by ChicagoBoy11 »

conjectures wrote: post #44
wirrbel wrote: post #11

I studied physics and this at a time when faculty gradually changed from blackboard-based lectures to powerpoint. The blackboard-based lectures were far superior to any other way of lecturing (in my view). Main benefit was in the speed of presentation. Writing on a blackboard takes some time, the lecturer is slow enough in presenting that you can really follow along, while not "standing still". What a contrast to pow…

I find another benefit of blackboard presentation is the order of information. The lecturer can build something up rather than simply showing the finished article and saying voila.

It's not that they CAN, its that they HAVE to.

A great teacher will be a great teacher with whatever you give them. But anyone not 100% tuned to that part of their teaching greatly benefits from some of the constraints that chalk gives them.

I'm a K-12 admin and once we had a HS teacher who was brilliant but her classes were often too difficult to follow for the kids. We just told her she couldn't use the powerpoint slides anymore. Yes, there was a huge discussion of timing and pedagogy and all of that, but ultimately, placing that constraint on her naturally put her at a much more equal footing to the students she was trying to teach.

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#93

Post by Syzygies »

JWKennington wrote: post #77
Syzygies wrote: post #42

My Hagoromo chalk and eraser notes: https://www.math.columbia.edu/~bayer/LinearAlgebra/Video/Cha... CNN is doing a short web video on this chalk, and I was interviewed last week. They particularly liked my custom attache case for carrying all my colors to teach. When I drew diagrams revealing Catalan number correspondences, they were quite worried that these pictures "weren't math" and I might be hoodwinking them. Th…

I too am enamored with Hagoromo; however, I wasn't able to get any of the Japanese chalk. I have been using the South Korean produced Hagoromo and find it quite nice. How do you think the Japanese vs. South Korean produced chalks compare? Good note about the microfiber! I'll have to try that. I've become increasingly frustrated with erasers. When it comes to washing the board, do you use a squeegee at all? I've found…

I used to carry a bucket and sponge, then a squeegee, spray bottle, and paper towels. Now I just use a damp detailing towel (not wet enough to drip), and water from the nearest source down the hall. Sometimes one needs to clean the towel and make a second pass to obtain a board that looks newly installed, but generally no squeegee is needed.

Wrong person to ask about holders. I like gripping bare chalk; my hand is too forceful for a holder.

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#94

Post by Syzygies »

jordigh wrote: post #90
Syzygies wrote: post #42

My Hagoromo chalk and eraser notes: https://www.math.columbia.edu/~bayer/LinearAlgebra/Video/Cha... CNN is doing a short web video on this chalk, and I was interviewed last week. They particularly liked my custom attache case for carrying all my colors to teach. When I drew diagrams revealing Catalan number correspondences, they were quite worried that these pictures "weren't math" and I might be hoodwinking them. Th…

I'd be surprised if you get five seconds on the final video. You might also be edited out in a way to make it look like you said something other than what you intended to convey. The Catalan diagrams will almost certainly not make the cut.

We'll see! From my experiences with reporters after being the math consultant for "A Beautiful Mind", I share your cynicism. This crew nevertheless impressed me. They'll certainly open with a closeup of my chalk attache case. The Catalan diagrams just didn't fit the prejudices that she imagines of her audience. I was interviewed with these diagrams behind me, so it will be hard to use anything I said without them appearing past my ear.

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#95

Post by thanatropism »

Bartweiss wrote: post #65
conjectures wrote: post #44

Earlier quoted context omitted.

I find another benefit of blackboard presentation is the order of information. The lecturer can build something up rather than simply showing the finished article and saying voila.

Working a project on a blackboard also encourages people to get the order right . It's surprisingly common to see Powerpoints which skip or reorder steps completely because the slide creator shuffled things around or worked backwards from the answer. I'm sure most people have seen professors skip numerous steps on blackboards, too, but in my experience there's at least a heightened awareness of what it looks like to…

What's best about black/whiteboards for me is precisely the nonlinearity. Numerous times I've seen professors realize near step 10 of the proof that something they said in step 3 isn't quite right; then a sidebar is opened and arrows start to be drawn to piece the puzzle together.

The point of going to classes versus studying alone at home is that you get to watch mathematicians doing mathematics. It's apprenticeship learning, the same as carpentry. Watching the professor reason and make mistakes and second-guess himself is invaluable. The typed class notes where everything is neat and theorems are numbered gives the impression of an immaculate birth that the student can't fathom arriving at. The best maths classes are the ones that teach you how to be a mathematician.

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#96

Post by thanatropism »

Syzygies wrote: post #42

My Hagoromo chalk and eraser notes: https://www.math.columbia.edu/~bayer/LinearAlgebra/Video/Cha... CNN is doing a short web video on this chalk, and I was interviewed last week. They particularly liked my custom attache case for carrying all my colors to teach. When I drew diagrams revealing Catalan number correspondences, they were quite worried that these pictures "weren't math" and I might be hoodwinking them. Th…

> Mathematicians like to believe that we're smarter than average, but we're actually just very focused.

Serious question: does this spell doom for people with ADHD?

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#97

Post by gowld »

thanatropism wrote: post #96
Syzygies wrote: post #42

My Hagoromo chalk and eraser notes: https://www.math.columbia.edu/~bayer/LinearAlgebra/Video/Cha... CNN is doing a short web video on this chalk, and I was interviewed last week. They particularly liked my custom attache case for carrying all my colors to teach. When I drew diagrams revealing Catalan number correspondences, they were quite worried that these pictures "weren't math" and I might be hoodwinking them. Th…

> Mathematicians like to believe that we're smarter than average, but we're actually just very focused. Serious question: does this spell doom for people with ADHD?

In my experience, yes, unless treated with amphetamines.

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#98

Post by gowld »

max76 wrote: post #88
moftz wrote: post #81

Earlier quoted context omitted.

If the professor just recorded the lecture, I'd imagine most students would never go to class again.

If no one goes to the physical classroom why not sell the same recorded lecture to a thousand people online instead of the 100 that fit into a classroom?

Or better yet, give it away for free!

https://www.edx.org/school/mitx

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#99

Post by gowld »

ChicagoBoy11 wrote: post #92
conjectures wrote: post #44

Earlier quoted context omitted.

I find another benefit of blackboard presentation is the order of information. The lecturer can build something up rather than simply showing the finished article and saying voila.

It's not that they CAN, its that they HAVE to. A great teacher will be a great teacher with whatever you give them. But anyone not 100% tuned to that part of their teaching greatly benefits from some of the constraints that chalk gives them. I'm a K-12 admin and once we had a HS teacher who was brilliant but her classes were often too difficult to follow for the kids. We just told her she couldn't use the powerpoint…

When you try to force could behavior by handciapping people, you also get utter failures like teachers with bad (or too-slow) handwriting who cannot succeed at conveying information via the arbitrary restriction.

Re: Mathematicians are hoarding a type of Japanese chalk (2015)

#100

Post by jeffwass »

wirrbel wrote: post #11

I studied physics and this at a time when faculty gradually changed from blackboard-based lectures to powerpoint. The blackboard-based lectures were far superior to any other way of lecturing (in my view). Main benefit was in the speed of presentation. Writing on a blackboard takes some time, the lecturer is slow enough in presenting that you can really follow along, while not "standing still". What a contrast to pow…

When did this happen? I got my PhD in physics in 2008 and other than the introductory undergrad classes, all other classes (that I knew of, at least) were still taught using chalkboard/whiteboards.

And I agree with a sibling comment on this thread. The speed of information is ideal with live ‘writing/derivation’, as you can follow along at the teacher’s own pace and write each step yourself.

I used to do his for my own section classes I taught as a TA. I’d come in with a small post-it size note of starting points, and just work brought problems without referencing anything else. Kept it down to Earth, and I think (or hope) showed the students there’s nothing insanely hard here, just lots of small bite-sized steps.

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