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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)

#71

Post by bluGill »

onemoresoop wrote: post #35
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…

In this day and age why not pay attention to what the prof is saying, take scarce notes and use a phone to take a snapshot of the blackboard and rewrite it later for better comprehension. One could also use audio or even video.

The act of taking notes is where at least half the value of notes are. Review latter is useful, but you can review the book. I cannot read my own writing, I still find I learn better when I take notes.

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

#72

Post by glaurung_ »

The college I went to had a mix of whiteboards and chalkboards. Even as a student I preferred the rooms with chalkboards. It seemed like the light on dark contrast and no glare made them easier to see.

I also find disposable markers to be a bit of an environmental horror. In the grand scheme of things maybe it's not that much waste, but replacing something like chalk with a thick plastic non-recycleable marker for little if any gain is disturbing.

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

#73

Post by OJFord »

JadeNB wrote: post #39
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…

> 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". While I love chalk, and miss it since my current university uses whiteboards (actually stupid @#@#* WallTalkers, despite our pleas), it's hardly the case that the two options are 'chalk' or 'Powerpoint'. Also, Powerpoint slide…

In EE blackboards were mostly replaced shortly before / while I was there a few years ago. Whiteboards are _vastly_ inferior for two reasons in my view:

1. Colours are harder to distinguish, or to see at all. Chalk is easy, even a brand new pen is difficult from more than a few rows back, possibly made worse by my colour blindness;

2. You can't go over an existing pen line. You can _sort of_ make it thicker (but typically remove part of it at the same time) but you can't draw a square and then go over one edge in red, for example.

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

#74

Post by ssivark »

leereeves wrote: post #61
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.

But slides have one big advantage: they can be posted online for later review so students can follow the lecture instead of taking notes.

So can copies of handwritten lecture notes.

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

#75

Post by erk__ »

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…

Thanks for the infomation, I don't think I have seen anything except Linex chalk while I have been at university in Denmark. So it is interesting that there is people who uses a specific type of chalk.

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

#76

Post by aliceryhl »

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…

I never found writing down things during lectures to be useful. If I didn't get something at the lecture, I can read it in the book.

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

#77

Post by JWKennington »

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 a sponge/squeegee combo to make cleaning quick.

A dimension of chalk usage that seems to be missing from your page - what do you think of chucks (holders)? Hagoromo chalk is quite wide (11mm) and it seems that most chalk holders are built for 9mm chalk. I use the Hagoromo branch chalk holders, they seem to have good grip. The other alternative I've found is to look for artist-oriented graphite or pastel holders.

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

#78

Post by rtkwe »

cr0sh wrote: post #67
scott_s wrote: post #57

Earlier quoted context omitted.

I think that all of my math teachers in middle and high school used projectors with transparencies. It wasn't until college that most math and physics was on black boards. The major benefit of transparencies is that the teacher was always facing the class . So they could just look up to make eye contact with students. I hadn't given it thought before, but I assume transparencies weren't as present in college because…

It might also be due to lighting. Overhead projectors require a fairly dark room, and only work well up to a certain size and distance. Much beyond that, their light gets too dim, and if it is a large lecture hall, you need a large projection with very bright light for everyone to see. Then there's off-axis people who might find a projector difficult to read. In a small classroom, both of these issues don't really co…

> large lecture hall, you need a large projection with very bright light for everyone to see.

And the hard limit on how bright you can make that is that the lecturer is staring into that light while writing so you can only make it so bright before it becomes painful or damaging. Anecdotally when I was in elementary/middle school we'd sometimes have to work things out writing on a projector and it was tough sometimes and looking up you couldn't really see because your eyes had adjusted to the brightness of the projector. Maybe they could improve the lenses to spill less light out but it wasn't back then.

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

#79

Post by stronglikedan »

aliceryhl wrote: post #76
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…

I never found writing down things during lectures to be useful. If I didn't get something at the lecture, I can read it in the book.

A lot of people, myself included, commit things to memory through writing. A lot of good lectures go beyond the books, so content can easily be forgotten. I even took notes while reading the books, lest I forget what I read.

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

#80

Post by onemoresoop »

bluGill wrote: post #71
onemoresoop wrote: post #35

Earlier quoted context omitted.

In this day and age why not pay attention to what the prof is saying, take scarce notes and use a phone to take a snapshot of the blackboard and rewrite it later for better comprehension. One could also use audio or even video.

The act of taking notes is where at least half the value of notes are. Review latter is useful, but you can review the book. I cannot read my own writing, I still find I learn better when I take notes.

For the better, take notes afterwards while listening to a recording and looking at the blackboard snapshots. However, I understand that this cannot be a regular practice due to time constraints but maybe this could be used for the classes that spark most interest, the knowledge crystallizes better with a few passes
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