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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)

#21

Post by magicalhippo »

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 found the exact opposite when learning math. I need to write it down, and when presented with Power Point I have to transform it into something I can understand, and that means I don't have enough attention left to really listen to the lecturer.

On the other hand, the lecturers that used a blackboard at my uni all had prepared the lecture, what they wrote was meant to be written in a notebook. They wrote it at a pace that could easily be followed. This allowed me to go over proofs as I wrote them down, and I could then ask right away if there was anything unclear.

I also found several typos (usually a sign error or a missing term) this way, something which would probably have confused me a lot if I didn't catch it until I got home.

So, for me, well-prepared blackboard lectures is preferable, at least for math heavy stuff.

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

#22

Post by Aromasin »

jerf wrote: post #20
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…

That certainly makes much more sense. My experience was primarily undergraduate, plus a years masters. I will admit, during the MSc chalk-board work was valuable during the seminars and labs, where it was much more design based.

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

#24

Post by 0xcde4c3db »

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

I think it's sometimes a mix of several alcohols, but that probably has more to do with ethanol being cheaper than with any issue of suitability or effectiveness. Recently, I've also seen "cleaner" that's definitely not alcohol-based and also doesn't work worth a damn.

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

#25

Post by klodolph »

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

It is definitely not just isopropyl alcohol. You can verify this yourself by looking at the MSDS. Whiteboards are non-porous, that's an essential part of how they function. The isopropyl alcohol degrades the non-porous layer on top and over time leads to ghosting.

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

#27

Post by lfowles »

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 once had a professor that would write on the blackboard with his right hand and erase with his left simultaneously. Quite a struggle to keep up with equations on those days he chose to fly through lectures like that!

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

#28

Post by erk__ »

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 feel like some things work on powerpoints and other onthe blackboard, for example maths work a lot better on blackboard. Some of our best lecturers had a powerpoint but they first showed the equations on them after they had showed them on the blackboard, which I found pretty good.

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

#29

Post by EamonnMR »

gnulinux wrote: post #19
nerdponx wrote: post #4

Earlier quoted context omitted.

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.

https://en.wikipedia.org/wiki/Isopropyl_alcohol#Safety

Yeah.

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