How to draw dotted lines on chalkboards, MIT style (2021) | Hacker News Reader

How to draw dotted lines on chalkboards, MIT style (2021)

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I was at school in the 80s and 90s in the UK and this brings back very fond memories of a highly eccentric Latin teacher I had, who mastered this technique and used it frequently. The other memorable thing about him was how he'd tell us he was going to do some photocopying and head off with no paperwork, only to return 5 minutes later still with no paperwork but smelling of pipe smoke.

Some more modern classrooms had the greenish boards that were a continuous loop that you could roll, but the older ones had black ones that were extremely heavy (maybe slate?). Some of them had a counterbalanced pair on ropes and pulleys in wooden runners, so that when you slid one up the other would come down. I remember in one lesson the ropes snapped and the front-most board came whistling down like a guillotine past the face of the maths teacher and landed with a bang like a gunshot. He was unhurt luckily but was extremely pale and shaken - understandably!

I too was at school in the UK during the 80s and 90s and don't have any fond memories. Maybe because it wasn't a school with Latin in the curriculum. I had two science teachers: a young one and one nearing retirement.

The young science teacher spent the whole lesson writing from his notes onto the blackboard, while the whole class just copied it verbatim. His only interaction was asking whether everyone had finished, before wiping one-half of the board clean to continue.

The other science teacher had us read from our textbooks all lesson, and his only interaction was to get annoyed when we made so much racket he couldn't read the newspaper. He always seemed the smarter of the two teachers to me.

I got the same grade in both exams.

I went to one of the best schools in England allegedly. We had a new English teacher who spent a whole year doing the silent notes on the blackboard thing. He would come in early so he could get a head start. We also had a PE/French teacher who couldn't speak French. Shit teachers are everywhere.

I was in a school in the UK during the 00s and I have OK memories. It had Latin in the curriculum, so I think we can conclude Latin does not correlate with fondness of memories.

The teachers used annoying 'SMART' boards and if they ever got board marker ink on them they would freak out.

I considered one of those rollerboards from Wilson and Garden, Ltd, in Glasgow, UK, for my home office. Somehow working with ipad+pencil is just not the same.

As a compromise, you can get blackboard paint, and paint any size of surface you want to be a blackboard.

You can also get magnet paint, so you can put up magnet thingies. I don't think blackboard paint is as durable as real blackboards, but then, different use cases.

This is SO satisfying to see and hear performed well: https://www.youtube.com/watch?v=l789l6np-qA

Be sure to turn the closed captions on!

Zdrrrrrrr drrrr drrrrrr zrrrr

Lost it at the all caps one

Brrr (dark magical spell) rr rrt

That sound is very unpleasant.

I still find blackboard + chalk to be a heinous combination. Is this just because my grade school used cheap low-grade chalk?

I do have a weird physiological reaction to 'fffffffff' friction sounds. A hard cheap pencil against cheap paper, making a similar raspy sound as chalk-on-blackboard, with cause me to reflexively (and uncontrollably) suck my lips in tight, as if protecting my teeth from the vibrations. Back in school, after a long homework assignment, my lips would get swollen from doing this. It doesn't happen with pen, doesn't happen with smooth pencils or soft paper. Apparently I'm not the only one with this weird thing.

>Is this just because my grade school used cheap low-grade chalk?

Most likely yeah. I remember reading here about the fairytale that is Japanese chalk and that US professors were hoarding it. I assume it must feel orgasmic.

We didn't have that kind of opulence in Eastern Europe. Chalk and blackboards here sucked ass, including the cleanup process students were responsible for. Schools switched to whiteboards and markers ASAP.

Although much easier to maintain, whiteboards and markers have shitty contrast, especially if light or reflections hit them at the wrong angle. Matte blackboards were much better at absorbing light and unwanted reflections which I guess is why they're still used today.

Hagoromo does feel pretty nice to write with. It’s thicker and it writes smoother than standard chalk. It also has some sort of coating on the sides so it doesn’t get everywhere. It doesn’t break easily when dropped.

It’s good but not hilariously better than decent chalk.

I find that because of the coating you have to pick a side that you’re going to write with, and this small amount of mental energy is a small roadblock. It also seems shorter than regular chalk, although this could just be that the pieces I use are used frequently!

As a Hagoromo-using professor: its biggest advantage to me is that it erases much more cleanly, so that after a few passes over the board you can still read the new writing instead of it looking like writing over half-erased writing.

That’s a great point that I forgot to mention. I’d reckon a large reason for this and its other benefits is how soft the chalk is.

I think I watched a video on it a long time ago and seem to recall that professors immediately break the chalk in half before using it. I don’t remember why.

I regularly use Hagoromo chalk on a personal chalkboard and I always break new sticks in half before use. For me, it feels more comfortable to use smaller pieces than large ones. It allows me to hold the chalk with more fingers, and avoids the awkward position where you have to hold the chalk like a pencil with a few inches of chalk resting on your hand. However, some friends swear by full, long sticks, so it's very much a matter of what you're used to.

Personally, I always was afraid of breaking the long chalk while writing, which would have caused the far end to fall to the floor and break into many small pieces. So why not be safe and write with a shorter stick.

I don't know anything about japanese chalk but in general you should break chalk in half because that makes the chalk not scratch with a high pitched sound when used.

While it's not manufactured by the same company anymore, a Korean company bought the formula and sells it on Amazon now! [0] So, you, too, can see what the hype is all about, if you want! At $0.39 per piece of chalk, it is, indeed, expensive. But, it is also a much different experience from writing with ordinary chalk.

---

[0]: https://www.amazon.com/exec/obidos/ASIN/B01HDNUXBW

> All Hagoromo chalks are well coated to prevent hands from coming into contact with chalk dust when using. Never have to worry about stained, dusty hands when using chalk ever again

You mean not having messy hands after writing on a blackboard is a thing? You mean my whole life was a lie?

FWIW, there are such things as chalk holders, also called chalk chucks.

(As a tongue-twister, do you now have chalk chuck shock? :)

I vaguely remember some pieces of chalk in my school having paper wrappers on them. Those were a bit less messy.

> I remember reading here about the fairytale that is Japanese chalk

Specifically Hagoromo chalk, I think

I probably read the same thing and bought some of the more recent Korean-purchased version, and it _is_ quite wonderful.

I've always hated whiteboards; when I leave something up on my chalkboard for a few days/weeks, I can still erase it. If I need more cleaning, water works. I don't need some foul smelling, expensive, concoction to clean the damn thing. (Yes, I know the "tricks" of toothpaste or drawing over the stains; the latter counts as "foul smelling, expensive", however.)

Any dust that gets on my clothes (never happens, but a common complaint), is removed with my hand easily enough.

Good chalk on a good board should sound like a light hiss, not a lot of 'ffffff'.

and then there is fingernails on a chalkboard...

> Is it just...

Definitely yes. Good chalk and good boards sound completely different.

I remember old blackboards made from a soft material, or a soft layer under the “black” part. These sounded very pleasantly, like the most thocc-y keyboards.

Newer boards came rock solid, and when they met a hard granule in a chalk, it made unbearable sqeaks and clacks.

I thought I was alone in this. Something about the scratch of pencil on paper always bothered me; I had to use the softest graphite possible to not go crazy.

Could be the low grade chalk. I remember a short video that talked about a Japanese chalk manufacturer shutting its doors, and professors from all over the globe were flocking to Japan to buy it or figure out ways to trade it because the remaining stock couldn’t be exported (a little fuzzy on the details here). Allegedly, the chalk was just that good.

In primary school I couldn't win; blunt pencils were a bad time, and trying to sharpen my pencil would lead to the tip breaking pretty soon after. Pens also get to me sometimes, I have one which is really nice to use and it puts out a lot of ink, but I'm not sure if that's it.

Stationary can become a great and not-overly-expensive hobby if you invest a little bit of effort in it. I wish I knew what I know now when I was going to school:

* If I use harder pencils("F" or "H" where the standard pencil is "HB" and softer pencils are "B"), they erase more cleanly, give more friction so I get better control, and break less. Going softer makes them dark but there's a big tradeoff involved in the other respects.

* When I was growing up gel pens were still pretty new and ballpoints were the best option for lefty ink writing in most instances. However, now pretty much everything is a hybrid with quick-dry ink. If I had to pick one all-rounder it would be the Uni 207 Plus+.

* The standard ruled filler note papers are mostly terrible - thin, with a crummy, uneven texture. This means that they can't be used with all pens effectively because roller or fountain ink will go right through. Getting anything slightly heavier and smoother(even a graph paper pad) makes for a better experience.

* To learn to hold pens and develop muscle memory, do a lot of blind contour drawing, and use the various different kids' art supplies to vary the process. The reason why this works well is because blind contours make you navigate the paper by feel alone, and the specific feel of each tool changes your approach - pencil, crayon, brush, marker, chalk all have differences in how they're best held. So you end up being very sensitive to the differences, which makes you better at drawing as well as using the most effective grasp for the task.

One technique to deal with shitty quality chalk/chalkboard that worked for me was to dip the chalk in water.

I went to a talk by a grad student historian who studied how mathematical ideas evolved in Europe roughly 1600-1900. He started his talk by quickly drawing a damn near photorealistic map of Europe on the chalk board. Very impressive way to start a talk and make it memorable. It really impressed on me how lecturing can be developed like a performing art.

I never leveled up my chalkboard skills, but there were definitely times when I distracted myself from proofs that wouldn’t work by learning how to make beautiful diagrams in latex + tikz. Beyond improving the presentation it’s a nice way to get a break from the words and symbols part of the work and blow off some steam.

> but there were definitely times when I distracted myself from proofs that wouldn’t work by learning how to make beautiful diagrams in latex + tikz.

I have never, ever, regretted coming to the table with eye candy like this. Were some of those investigations the most "profitable" thing to be working on at the time? Probably not, but a good, clean visualization buys you so much cred with both your audience and yourself.

You can waste ours and hours to something in tikz which could probably be done in 30 minutes with SVG. Sigh.

Very similar to "chattering", a technique in pottery for adding surface texture. In that the surface marking implement is used in a way that elicits rapid reciprocation leaving a periodic pattern in the clay surface.

Examples, https://youtu.be/FBxhkRu9imA using a long springy tool, https://youtu.be/W_P-L0axcqs using a short tool that pivots.

Check out explanation by Walter Lewin https://www.youtube.com/watch?v=GhawwXcQsUs

I was surprised there was no mention of him in the text. There's more of him on YouTube: https://www.youtube.com/results?search_query=walter+lewin+do...

If I recall correctly, Walter Lewin could also freehand draw perfect circles on the chalkboard

I have to ask. Why is it "white"-board vs. "chalk"-board? Back in elementary school, I learned to call the former "black"-board.

To me at least, the different types are easy to understand.

White-board - the color of the board is white, it is used for dry erase markers.

Black-board - the color of the board is black, it is used with chalk.

Chalk-board - the color of the board doesn't matter, it likely uses chalk to write with and is therefore a "blackboard" as well.

Chalkboards are green, it just happens that the name also encompasses blackboards.

Regional variation? When I was growing up (in California, in the 1970s and 80s), we called them chalkboards because, you know, you used chalk to write on them. Also, they were often green.

Do you call it 'soda' or 'pop'?

Or "tonic" (which was already a somewhat archaic term for soda generally in the Boston area when I was going to school). Boston had a number of those. Frappe was another--which you still see now and then at old-timey ice cream places. (A "milk shake" was just flavored milk.)

"pop" where I grew up in the midwest, but now that I'm in/near Atlanta, it's mostly "coke" regardless of variety.

> Do you call it 'soda' or 'pop'?

Soft drink

> Do you call it 'soda' or 'pop'?

'coke'

"Soda pop" is also a valid answer.

'Obesity juice'

"Fat-free"

I was born in the 70s, raised in Oregon, and we called them chalkboards. "Blackboard" sounded old-timey to me, like something you'd hear on Little House on the Prairie. A Google search result points out that green became a common color for chalkboards, and in retrospect I think most of mine in school were green.

More googling says that the original blackboards were slate. The green ones were porcelain.

Our green ones varied in quality and material. Most of them seemed to have some cheap coating that was sometimes torn by chalk; after being torn, the edges of green coating seemed stretched like thin plastic. Some of the green ones, the teachers actually liked. Maybe those were porcelain?

Also had blackboards at some of my schools. They seem to last forever without much care.

Not an explantion, but I do remember when they first arrived (there was one the year I began high school -- new physics teacher got to set it up how he wanted) and no new ones when I left. I also saw then appear at MIT, again, mainly new construction/renovation.

Chalk boards came in black or green. That name is lost in history, to me. Whiteboards were kind of a shock by comparison -- bright rather than dark -- so it did seem natural. "Marker board" sounds funny now, though it makes sense ("not chalk") but I suppose had it caught on it would be normal. I've only seen "dry erase" used on packages so I assume it's a branding issue.

While the one at my HS was the first one I'd seen (and, seemingly the first any of my classmates had seen, as it was a minor topic of dicussion) I think we'd at least heard of them. This was 1978.

"dry erase" means the ink comes off even when dry, as opposed to a permanent marker.

Also, after a long time, even dry erase needs toothpaste to come off.

I've never heard of using toothpaste, but one can take off old dry erase or even permanent marker by going over it with fresh dry erase, then erasing normally.

A good hint, but toothpaste is awesome.

Not only does it keep the cavity creeps away, it also can remove stains in wood finishing.

I once had a bottle of alcohol spill a little, and it discoloured the wood table stain. Toothpaste fixed it.

And the room smelled minty after, too!

> Back in elementary school, I learned to call the former "black"-board.

Same here. It’s still called black board in my part of the world, I think.

In português it's "quadro branco" (a white board/rectangle/frame on the wall or on a stand) and "lousa" (which refers to the material and/or its colour and texture). I think "chalkboards" and "lousa" can be black, grey, blue, brown, purple, red, or green, but maybe "blackboard" can only be black.

"Lousa" is more of a PT_pt thing. In PT_br, "quadro negro" was more usual, but most of them were painted dark green, go figure!

In Spanish we call a blackboard a "pizarrón", which references the slate its made of.

Because many chalkboards are a greenish color instead. Even slates are often more dark greyish than black.

In the UK they still call them "blackboards", I've never seen a green one over here.

Yup, as an Aussie my understanding is that UK English would call it a blackboard whereas US English would call it a chalkboard. AU English therefore followed the UK, regardless of if they're the dark angels-esque green or fully black colour.

I've pretty much always heard it as blackboard in the US though I wouldn't do a double-take if someone called it a chalkboard. I'm pretty sure I've seen green variants but not at all commonly.

I prefer dark-mode and light-mode.

Ronald Susskind uses a white board and calls it a black board

Ronald!? Leonard... now I can't edit it and forever I will look like an idiot.

Just tell people it's his muddle name.

I've never heard 'chalkboard' before fwiw.

Because some chalk boards are green

Isn't it the same like whitelist and blacklist ?

Hypersensitivity to the word "black".

Comments about "chalkboard" being more accurate should only be accepted if the proponent also uses "penboard".

I think you are projecting your own hypersensitivity into your understanding of the topic.

Green chalkboards, like my schools had as a kid, were not black.

https://en.wikipedia.org/wiki/Blackboard points out "Green porcelain enamel surface, was first used in 1930, and as this type of boards became popular, the word "chalkboard" appeared. In the US green porcelain enamelled boards started to appear at schools in 1950s."

To double-check, see the Google Ngram comparison at https://books.google.com/ngrams/graph?content=blackboard%2Cc...

The use of "chalkboard" doesn't really exist before the 1940s, and increases rapidly in the 1950s, reaching the current rate (of about 50% of the usage of "blackboard") in the the 1960s.

Blackboards are not black, they are grey; robin red-breasts do not have red breasts, those are orange; Redheads do not have red hair, they have orange-brown, and so on. So why is it that black is renamed on the grounds of accuracy?

> I think you are projecting your own hypersensitivity

I'm puzzled by this, could you elucidate? I'm with James Brown "Say It Loud – I'm Black and I'm Proud", I don't see black as a negative, so I don't see why the word should be avoided.

> Blackboards are not black, they are grey

Yes, and tennis shoes aren't only used for tennis.

What you wrote is not correct. First, I assume you are not making the technically-correct-only assertion that since everything, including Vantablack, reflects some light, it isn't truly black but only a dark shade of grey.

Quoting Wikipedia, "Blackboards were originally made of smooth, thin sheets of black or dark grey slate stone". That's "black" and "dark grey".

But you don't need to take Wikipedia's work. We can look at books from a century ago and read a book where they improvised a blackboard using black paint: "This space was carefully sandpapered and immediately after received its first coat of black paint, prepared with oil, which served as a foundation. After 24 hours, another layer of the black color followed, (this time without oil) and finally, in two more days, the black brush completed, from every standpoint, a perfect blackboard." https://archive.org/details/jstor-3406078/page/n1/mode/2up?q...

Or the 1905 book "Nelson's blackboard drawing" which mentions "So long as the black surface of the board is visible, the sketch is quite conventional" at https://archive.org/details/b1625318/page/n121/mode/2up?q=bl... . (As an aside, there are some excellent chalk drawings in that book.)

Thus, black surfaces for chalk use in a classroom have long been referred to as "blackboards."

You can see the transition to "chalkboard" in the 1950s (emphasis mine in the following) in a 1955 publication saying "And don’t overlook the old standby, the chalkboard. Notice that we refer to it as a chalkboard, since it is not black. A green board and yellow chalk will not produce the halo effect that results from using white chalk on a blackboard. You can make a simple and inexpensive chalkboard by painting the smooth side of a piece of tempered masonite with green chalkboard paint." https://archive.org/details/CAT10679308/page/2/mode/2up?q=ch...

As well as in this 1953 newspaper article titled "Britain Bans Old-Fashioned Blackboard For The New Colored Chalkboard", wherein we read how "a slab of black on the wall has a tendency to create a dark, depressing, uncomfortable and gloomy atmosphere", and how they will be replaced "with a 'chalkboard' in some one of nine brighter colors" https://archive.org/details/1953-04-11-1953-04-30/page/n167/... .

The trend continues, like this 1962 comment that "The chalkboard (blackboard) is one of the oldest graphic or visual instruction devices. The earlier slate blackboard has now been replaced by white, green, or yellow satin-surfaced or glareproof glass or plastic chalk-board." at https://archive.org/details/audiovisualmater0000unse/page/66...

By the 1970s you can see Sears referring to an "old-fashioned blackboard" as a "black chalkboard" at https://archive.org/details/1970-1979-sears-wishbook-toys_20... and at the bottom of the page is a flip chalkboard with described as blue on one side and black on the other.

> So why is it that black is renamed on the grounds of accuracy?

As they said in the 1950s, "we refer to it as a chalkboard, since it is not black."

While your "hypersensitivity" hypothesis doesn't explain why the changing usage started in the pre-Civil Rights era of the 1950s, and including the UK.

> could you elucidate

I think you are hypersensitive to the idea that others are hypersensitive to using the term black.

I think you are so hypersensitive that you dismissed counter-evidence out of hand, without further examination.

You could be right, but using your favourite n-gram viewer, it looks like there is a relationship

https://books.google.com/ngrams/graph?content=%28chalkboard+...

Any thoughts on that apparent correlation? My (implicit) assertion was: in times of racial tension, people avoid(ed) using the word 'black' not wanting to appear racist. That seems reasonable to me, could there be some causal relation in the other direction?

There's an old phrase: "Correlation is not causation."

"TV" to "civil rights" - https://books.google.com/ngrams/graph?content=TV%2C%28civil+...

"Plastic" to "civil rights" - https://books.google.com/ngrams/graph?content=plastic%2C%28c...

"Pakistan" to "civil right" - https://books.google.com/ngrams/graph?content=%28Pakistan%29...

The site https://tylervigen.com/spurious-correlations shows a lot of spurious correlations.

What I did instead was present a claim (Wikipedia links to https://books.google.com/books?id=sl5GAwAAQBAJ&pg=PT45 and also describes the technology that made colored chalkboards popular), then double-checked that Ngram was consistent with the claim.

> That seems reasonable to me

Yes, that's because your hypersensitivity is kicking in.

It's causing you to reject the actual reasons given at the time in favor of your pet theory.

I've presented two direct quotes from the 1950s saying the reason for switching to "chalkboard" is because the new boards were not black.

You instead prefer to think these sources were hiding the truth, apparently in order to cover up hypersensitivty to the word "black".

Another problem with your pet theory is that in the 1950s black people were generally referred to as "colored" or "Negro". "Black" didn't start replacing "Negro" until the 1960s. Your James Brown citation is from the late 1960s, for example.

Your belief is that large numbers of people in the 1950s were so hypersensitive to the word "black", because someday in the future it might be used to refer to colored people, that they switched from "blackboard" to "chalkboard"?

While at the same time large numbers of people enforced racial segregation and discrimination.

Your pet theory would need a LOT of historical supporting evidence to hold any water. So, where's your evidence?

    I've presented two direct quotes from the 1950s saying the reason for
    switching to "chalkboard" is because the new boards were not black.

There's an old saying: "One swallow does not make a summer". It means that one should be careful extrapolating from slight evidence.

So how does your pet theory handle that the same phenomenon, a shift from blackboard to chalkboard, also happened in the UK (which also had a period of co-incident racial tension, albeit not as extreme as in the US) while, as others have mentioned, green blackboards are rare?

My point was to demonstrate that your "hypersensitivity" hypothesis has no evidentiary basis, and in fact runs counter to easily available evidence.

I believe I have done that, in way that other HN readers can easily verify for themselves.

Had you researched the topic yourself you would find more supporting evidence for my pet theory. I only presented a sampling of what I found, to keep my comment from being a wall of text.

Your saying doesn't even apply to you as you have not presented any evidence, not even a single feather.

As you don't seem to care, my interest here is done.

I don't know, I remember people talking about calling them chalkboards instead of blackboards in the UK 25 years ago, back when it was "political correctness gone mad". We don't have green chalkboards at all in the UK. They're all black.

In researching a sibling comment, I found a 1953 newspaper article saying "Britain Bans Old-Fashioned Blackboard For The New Colored Chalkboard" at https://archive.org/details/1953-04-11-1953-04-30/page/n167/... .

The reason given is "a slab of black on the wall has a tendency to create a dark, depressing, uncomfortable and gloomy atmosphere", and they will be replaced "with a 'chalkboard' in some one of nine brighter colors"

Amusingly, the Collins English Dictionary (3rd edition) defined "chalkboard" as "a U.S. and Canadian word for blackboard." at https://archive.org/details/isbn_9780004332864/page/268/mode... . Archive.org says it's from 1981 but I can't find a date in the book.

And in "An Assembly Collection" by Joan Hasler, Headteacher at Dover Grammar School for Girls, (1986) is reading 128, titled "Green Blackboards"

  The school is up-to-date.
  Proudly, the principal tells of all the improvements.
  The finest discovery, Lord, is the green blackboard.
  The scientists have studied long, they have made experiments;
  We know now that green is the ideal colour, that it doesn't tire the
    eyes, that it is quieting and relaxing.
   ....

I also found mention of a "green blackboard" in Comedians, a 1975 play by Trevor Griffiths taking place in 1970s Manchester (see https://en.wikipedia.org/wiki/Comedians_(play) ): "his room, on the ground floor, is smallish, about a dozen chipped and fraying desks, two dozen chairs set out in rows facing the small dais on which stands the teacher’s desk, with green blackboard unwiped from the day’s last stand beyond." - https://archive.org/details/comedians0000grif_p3e8/page/6/mo... .

So it appears at some point there were at least green blackboards in the UK.

I've seen green blackboards in UK universities, pretty rare though (and still usually called blackboards).

Great research. Obviously I was not being 100% literal when I said we don't have green blackboards (heh) in the UK. I'm sure somewhere someone has one, but I've literally never seen a single one so they must be exceedingly rare.

Very interesting comment anyway; thanks!

He links to the whiteboard post, which is interesting because it shows the toothpaste technique for cleaning them. The best buy ever for me was this large, glass whiteboard which is so much easier to erase and clean than a normal whiteboard: https://www.glasswhiteboard.com/

It's always somehow funny to think about toothpaste and how it is actually an abrasive, a colloid of tiny solid particles, rather than a surfactant like most other everyday cleaning agents. Which is why it can be used to polish headlights, clean whiteboards, etc.

Straying a bit from the topic, but those 'magic eraser' home cleaning products work on laminated plastic, like you find on day-planner erasable calendars.

Porcelain whiteboards are nice, I've always managed to get them very clean with just rubbing alcohol.

Is there any concern about chipping or even breaking with the glass whiteboards (if, for example, it somehow falls on the floor, eg during moving)?

No, you just have to be careful when installing them or reinstalling/moving them. Make sure it's solidly mounted and there's no problem.

Yes. I got one of these at home and they're awesome. Zero regrets.

So much better than the whiteboard I have in my office at work.

Those create a shadow of what you write, because the glass creates a gap between the writing and the white background, right?

One fun thing about this. There's this teacher that I met in middle school who also knows this trick. I'm Chinese, that guy too. He was old (in his 70s) and he definitely didn't know how MIT does it so this is a common trick around the world in some way.

Great video showing the process of learning the technique https://youtu.be/hbWeSHbL-rM

Yep, these videos have been around for some time. Good stuff!

https://youtu.be/RqC7QpNrprg

If a picture's worth 1,000 words, here a video would be worth 1,000 pictures.

https://www.youtube.com/watch?v=l789l6np-qA

How is this MIT style? Many people using chalkboards all around the world do this.

This is from a blog by a student blogger for MIT Admissions, so it's explicitly meant to be MIT-centric, and probably the author hadn't seen it done anywhere else.

MIT as an institution is a bit over-self-referencing sometimes.

Because MIT doesn't know about them, but they know about MIT!

I have a theory that the declining respect students have for teachers in our modern age can mostly be attributed to the extinction of chalkboards in modern classrooms and the increasing reliance on wimpy whiteboards or even projectors.

The difference when entering a classroom with a chalkboard versus a whiteboard is profound. A black chalkboard is vast and commanding. The human eye is drawn to the empty black space by years of evolution, whereas bright whites make one squint and look away from the glare. The black space makes one feel like something amazing (or terrifying) is about to happen.

The loss of respect for a teacher compounds when they rely on technological equipment that frequently fails and exposes them as a tech-illiterate fool, leaving a class staring at a blank blue projection while their idiot teacher grovels and prays to the tech Gods to just make things work.

But when a teacher, no, a professor, lifts a piece of chalk and slams its point to the board it makes an audible sound, loud enough to be detected but quiet enough that conversations will cease to hear what comes next.

And as the teacher writes on the board and manifests symbols onto what was once an empty space, all students will see the teacher as a creator of universes that can be wiped away from existence as easily as they were spawned. And you better write down what these symbols and drawings mean while you can, because a teacher that uses a chalkboard is a teacher that doesn’t give a fuck about giving you a copy of slides or notes for you to review.

The chalkboard is a timeless instrument. It worked 1000 years ago and it will work 1000 years from now. There’s no markers to dry out, no technology to be obsoleted. There is simply the brutal violence of stone upon stone, imparting wisdom for those who seek education. And those who wield the chalk are not “teachers”, but rather Masters of Knowledge, whose profound wisdom is reflected everyday in their choice of presentation.

> all students will see the teacher as a creator of universes that can be wiped away from existence as easily as they were spawned. And you better write down what these symbols and drawings mean while you can

Even v.s. a whiteboard, there is something poetic about symbols being wiped away to dust of the earth rather than a vivid blue smudge. And that dust becomes part of the institution. I spent a little time around high level physics students in their natural habitat and there is still a strong feel of it being clung onto tightly by professors and (perhaps LARP-ingly) students dedicated to the culture.

> I have a theory that the declining respect students have for teachers in our modern age can mostly be attributed to the extinction of chalkboards in modern classrooms and the increasing reliance on wimpy whiteboards or even projectors.

I think the transition away also correlates with hermetically seal buildings and using central air everywhere.

I learned this technique in the mid 70s, but I didn't attend MIT. I still remember a math class in 1973 that was sort of rowdy. One of the students was presenting. He wanted to draw a circle on the board, but there were actual, occasional, spitballs. If he took his eyes off of the class he would have been a sitting duck. Not to be deterred, this student, Kem, stood at the chalkboard facing the class with a piece of chalk behind his back, touching the board near the bottom. He swung his arm out and up and, at the same time, began to pivot around. His chalk went up to the top of the board, all the way around, and back to the bottom just as he turned to face the class again. The circle was elegant, no one had time to launch a spitball, and he gained another level of respect in the class - he already had a lot.

The look of the chalk on the board in the photos there is just lovely. I often think about getting some high quality board and chalk for my home office, but then remember we have cats so adding ANOTHER source of dust is maybe not the best idea.

But chalkboards > whiteboards all day long.

This is why I read this site.

As I was going down the dotted line chalk rabbit hole I ran in to this: https://www.youtube.com/watch?v=eAhfZUZiwSE

Chalk boards are very visceral, Bringing a chalkboard instead of powerpoint when giving a presentation, makes for a much better presentation, A whiteboard is almost as good but does not have the same impact as a chalkboard.

One big part is that writing speed gives a natural limit of how fast the material can be presented.

With PowerPoint it’s easy to lose the audience, especially in math heavy stuff where taking notes really helps with understanding.

If the presentation is in PowerPoint, there is no way I can keep up.

While I agree in principle, I can tell you from extensive first hand experience on both sides that it's extremely easy to lose the audience with math heavy content on a blackboard too.

The only thing that I found to be really useful is for the students to already be familiar with the content (having actually prepared for the lesson), and the live session only reviewing it and then focusing on the deeper or most confusing parts.

Of course - what also helps is that writing speed with chalk is somewhat slower than writing speed with pen & paper, so that gives the audience some opportunity to catch up.

In university I installed a rather large sheet of acrylic on the wall in my dorm room. I then used "liquid chalk" markers to write on it.

Acrylic and the markers were more expensive than other solutions, but they could be erased either dry with some piece of cloth or a little bit of water.

Might be another option for anybody looking into that topic.

edit: That solution was not magnetic, though. I installed a magnetic strip on the side for that.

Nowadays that dark mode is in vogue, chalkboards should get a renaissance over whiteboards, right?

My electronics instructor did this really well. He would use multiple colors of chalk and draw dashed lines perfectly, also just as fast as he could draw a normal line.

Really nice to see it done well. I never used chalk enough to develop tricks or even proper technique.

People do this all over the world. How come it is MIT style :-)

I suspect you could make a simple dotting marker for whiteboards by taping an eraser to a whiteboard pen.

I release this invention into the public domain for the good of mankind.

> there is one really, really cool thing you can do on chalkboards that you can’t on whiteboards: make dotted lines

Seriously?

I believe the context makes it clear what is meant. Obviously you can lift the pen, move it a bit, put it down and so on, and create a dotted/dashed line on a whiteboard.

The things here is that there's a technique to make the chalk "skip" on its own, by finding some kind of friction equilibrium/magic point while doing a normal stroke so you don't need to manually control the point of the chalk to form each dot.

Really really cool.

That was my first reaction.

Then I’ve watched this from a sibling comment: https://www.youtube.com/watch?v=l789l6np-qA

Yeah you can’t do dotted lines on a whiteboard.

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