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Mathematicians are hoarding a type of Japanese chalk (2015)

gizmodo.com

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

#11

Post by wirrbel »

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 powerpoint presentations where the lecturer paused for a minute or two to let students read the equations. Either time was not enough, or you'd start to get bored.

Until I graduated at the end of my 5 year program, I tutored freshmen students. Towards the end of my time at uni, they almost exclusively had lectures with powerpoints. I sat in one of the into lectures and what had been a good introductory course to classical mechanics had turned into a mind-numbing powerpoint karaoke show.

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

#12

Post by dsfyu404ed »

majewsky wrote: post #9
781 wrote: post #2

> “Maintaining a clean whiteboard is much more of a pain,” he said. There’s the cleaning fluid, which costs money, and the chemicals can cause health problems. A clean blackboard is not that fun either. To clean it nicely you need to sweep the whole of it down vertically with a wet sponge. This requires a water source and it's a messy deal. In high-school there was a daily designated pupil who was responsible for wip…

When I was studying physics, I had a calculus professor who was popular among students for his good use of the blackboard. He would write a ton of text (about 20-25 sqm per 90-minute lecture), but everything was really tidy and well-organized. (He held the same lectures that he gave for the last 20 years, so I guess he got some insane amount of gradient descent going on over time.) Anyway, for the cleaning, he had a…

>He held the same lectures that he gave for the last 20 years, so I guess he got some insane amount of gradient descent going on over time

I took Calc 2 with a lecturer like this. She had been working there for a few eternities and could probably have taught the wall how to integrate. She had a reputation of being the "easy" professor but after comparing with other students it turned out she actually assigned substantially more work and covered the material faster. Her quality of teaching was just so highly refined that it made the work easier.

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

#15

Post by Aromasin »

I had one lecturer in my 4 years at university that only used a chalkboard, and most pupils despised him because the pace as which he wrote far surpassed the rate at we we could sensibly copy notes. We wrote it out, but it gave little time to actually consider the concept we were learning. The rest of my lecturers all used PowerPoint presentations for the most part, in conjunction with print-outs so we could follow along on a projector and write notes/annotations on the provided sheets.

In my eyes, a hand-out + computer notes (which can later be emailed to the pupils) is by far the superior teaching method for most students. This is of course just personal preference, but I much prefer simply sitting and listening to the teacher while occasionally asking questions - taking in as much as I can, then copying up the notes later using material provided by the lecturer so as to commit it to memory. Frantically writing out the notes during the lecture, then going home and trying to eek out some sort of understanding from them just never sat well with me.

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

#16

Post by b_tterc_p »

Porcelain whiteboards are, in my opinion, far superior to chalk. Color, distinct lines, easy to clean with just water (completely with no marks). Those who complain about whiteboards usually are only familiar with melamine boards.

I got a big porcelain board for 5 bucks on eBay because one corner was dented. Best purchase of my life.

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

#19

Post by gnulinux »

nerdponx wrote: post #4
781 wrote: post #2

> “Maintaining a clean whiteboard is much more of a pain,” he said. There’s the cleaning fluid, which costs money, and the chemicals can cause health problems. A clean blackboard is not that fun either. To clean it nicely you need to sweep the whole of it down vertically with a wet sponge. This requires a water source and it's a messy deal. In high-school there was a daily designated pupil who was responsible for wip…

Also the "cleaning fluid" is just isopropyl alcohol

Is inhaling small amounts of isopropyl alcohol safe? I found conflicting information online. Apparently it's also used for pipe and vape cleaner.

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

#20

Post by jerf »

Aromasin wrote: post #15

I had one lecturer in my 4 years at university that only used a chalkboard, and most pupils despised him because the pace as which he wrote far surpassed the rate at we we could sensibly copy notes. We wrote it out, but it gave little time to actually consider the concept we were learning. The rest of my lecturers all used PowerPoint presentations for the most part, in conjunction with print-outs so we could follow a…

The optimal teaching approach may depend on the level of the material, too. Slides & notes mailed to students may be a great option for "routine" math courses, things taken by a ton of different majors, where the paths are ground so smooth by the millions of feet traveling it that the entire class can be called in advance by even a fairly green instructor, almost down to the questions they're going to get.

As you get into higher math, though, the chalkboard becomes more important, because it's a lot more like working it out in front of the student. The class is far more likely to ask questions that are going to consume a couple of boards of scribbles to answer, and the professor may not be able to anticipate it all in advance. Trying to do this on a slide is very inconvenient and I'm still yet to see a computer interface in common use that can pull it off at all.

Many of those classes I took were actually hybrid; there was a core set of projected slides that could be mailed out (though they weren't always) that set the agenda and gave the basics and results, but there was a lot of chalkboard use as well, since as long as the room is even modestly large, there's no particular need to use just one or the other.

Graduate-level graph theory in particular used the chalkboard pretty heavily for what were essentially impromptu animations, between the numbers being added to a diagram as whatever algorithm we were learning about progressed, and the gestures being used by the professor.

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