This discussion reminded me of my best Diff Eq prof. He would start each lecture by putting a small clock on his podium, and starting at the precise time listed for the start of the lecture. Then he would leap into action, chalk dust flying around him as he explained the subject of the day. He would often go through more than six full-size chalkboards, having a student erase a few chalkboards behind him so he could return to use the first chalkboard when he ran out of room on the sixth one. Then at the precise time scheduled for the end of the lecture, he would take the clock off the podium and leave the room.
You could often see him walking around campus, covered in a fine white dust, looking like a ghost.
It's been 30 years, and I couldn't remember his name, but man do I remember his lectures.
Update: after typing this, I searched for him, and unfortunately found him almost immediately. He just passed away, and there was a memorial to him on the front page of his math department: https://www.math.fsu.edu/DepartmentNews/Articles/Fac_Nolder....
I note this line from the memorial: His students marveled at his ability to draw a perfect circle on the blackboard with a single stroke.
My crazed DQ Prof was an excitable Russian who worked in a classroom with a chalk board that wrapped around the entire room. He'd start on the right side of the door and end on its left side. Everyone had to rotate their desks during class as he worked his way around.
As a teacher that uses chalk and white boards I can heartily tell you that chalk sucks. It's messy on your hands and cloths, it breaks and is difficult to erase from the board. White board markers are so much nicer. The criticisms of markers seem to be, from the article:
You can't tell when they will run out. This is not true, they fade out not stop suddenly. Also, it is always possible to carry a spare marker or two.
Hand writing is worse with markers. Then look at what you've written and make it better.
White boards deteriorate faster. I currently use white boards that are a sheet of reinforced glass pained white on the reverse face. They've been installed for 10 years and look the same as they the day there were installed.
Permanent markers destroy a whiteboard. The glass boards make it a little bit of work but it instant destruction.
Chalk is less damaging to the environment than marker pens. This is true but can be mitigated with re-fallible pens.
Special "chemicals" are needed to clean a white board. The chemical that I use is water in order to make the cleaning rag damp. The same as I use for chalk.
If you leave writing on a whiteboard too long water won't do the trick and you'll need something stronger, like isoproplanol, or one of the many purpose mixed cleaning sprays
"chemicals" isn't inherently bad of course, if that needs saying. Don't drink the cleaning spray and you'll be fine
My experience was that once you use something more stronger than water, you have to continue using that substance.
Alternately, whatever chemicals are in the marker ink will dissolve previous marks and leave the whiteboard surface intact. Just right over what was written before and it will melt
It's like writing on paper vs writing on a digital tablet. The difference in tactile feedback leads to better handwriting, at least for me.
I'm curious about the phenomenon they mentioned of "circles being smaller with markers". I definitely noticed that when teaching my overall font size decreased on markers vs. chalk, even when using the skinny chalks. But the effective tip size even with small chalk is larger than that of whiteboard markers. So I wonder if we had big ass whiteboards with big ass tips on the markers if the writing style would be more similar. Or if it's more a function of the resistance you get with chalk+chalkboard. Could we make a whiteboard+marker that had more resistance? Like some hall effect or something. Sounds too complex relative to just using chalkboards.
That being said, a downside I didn't see mentioned was chalk dust. I have asthma but still prefer chalk, but I did not appreciate having to pound the dust out of the erasers when I was in grade school. I wonder if they could make the chalk magnetic and have magnetic trap at the bottom or something. But again too complicated.
> Could we make a whiteboard+marker that had more resistance? Like some hall effect or something. Sounds too complex relative to just using chalkboards.
I think that whiteboard vs chalkboard is just personal preference/cultural, and that the explanations in the article are just trying to justify it (which is totally fair IMHO). So I don't think that there's any need to "fix" that problem with whiteboards.
My hand writing is poor and my handwriting with a stylus is worse but screen annotations on zoom have been life changing for me at work. I don’t really care that I cannot write legibly. Quick iteration on diagrams is king.
I did not appreciate having to pound the dust out of the erasers when I was in grade school.
I wonder if they could make the chalk magnetic and have magnetic trap at the bottom or
something. But again too complicated.
The Russian solution is to use water - wipe the board with a wet sponge.
The german way seems to be a wet sponge followed by a squeegee to wipe off excess water. Here's a masterclass from Frederic Schuller (and a rigorous advanced course in quantum mechanics)
Pounding the dust out of the erasers was something American students often found fun, especially as elementary school students; this is referenced in the Tom Lehrer song "New Math": https://www.youtube.com/watch?v=UIKGV2cTgqA
In my school, the board was erased many times throughout the day with erasers, and then with water only at the end of the day so it would be "pristine" the next morning.
If you wipe with a sponge, you can't really go on to use it immediately can you? Like you can't write well on a moist chalkboard?
I had a great calculus prof who would wash all the chalkboards halfway through our (3-hour) class, and dismiss all the students for a 10-minute break while the boards dried.
I've had teachers that'd waft a binder at the board while continuing to talk. you can get a decent part of the chalk board dry in under a minute doing that. It's not like you're getting the board soaking wet either. A whiff of water is plenty to clean the board.
Edit: note you can also write on a wet chalkboard just fine. The tactile experience is just a little worse.
Wait, you don't use water?! As a German I kind of thought that's normal everywhere, dip the sponge into water, clean the blackboard. Slamming dusty sponges together sounds.. very dusty indeed.
Well, I only ever cleaned them fully in grade school. In undergrad I TA'ed on whiteboard, in grad school it was unfortunately all whiteboards. Except for the rare literal "chalk talk" mini-conferences I was fortunate to attend, where I just erased what I had at the end, no full cleaning. So, I guess I just never "saw how the sausage was made" and implicitly assumed the worst.
Or my grade school never knew better, which is quite possible given its size/location. Or they thought it was funny to make kids deal with all the dust?
Strange question - has the "submitted at" times been edited on this post and all the comments here? I swear I read everything on this submission, including the comments, several days ago, but nothing here is longer than a few hours.
Actually, google search agrees with me - if you search for the title here + hackernews, it says that it saw this post and several of the comments 6 days ago (apologies that I can't link to the cache as this is no longer a feature of Google).
Why are all the post and comment times here saying less than a few hours ago?
Unlike Reddit, the ordering of HN posts isn't only a function of the numbers of votes, number of comments, and time. Some other moderation activity can cause a front page post to suddenly be buried many pages deep.
I did all my undergrad in ink, and I loved it. Christmas time allowed me to use red and green and brown markers on my tests. The ball point pens had less friction, and I could write faster. Sometimes, an incorrect answer would still get points as I did not "erase" what I had previously written.
> Conrad also pointed out that if one accidentally applies permanent markers on a whiteboard, then the board would be “instantly dead,” a nightmare not applicable to chalkboards.
Not so.
Like dissolves like. You take a dry-erase marker and over-write the permanent, and then wipe both off.
When I saw the OP's headline I thought "because mathematicians think with chalk the way I think with code". One of the reasons why I Loathe and Detest LLM-based development is because I've developed the (potentially very bad) habit of working through my ideas with (sometimes heavily commented or literate-programmed) code—and LLMs basically take that workflow away from me almost entirely.
One of my math teachers in university always brought with him a dry sponge in a small blue bag. (a lighter sponge that you don't wet before use). Brilliant lecturer.
maybe a wise use of technology?: never adopt a higher complexity tech when a lower one fit well.
And white boards are less clear (to me) and markers dry (often in the worst moment).
And about slides... very easy for prof, but i cannot copy a slide, always follow the reasoning, so having the things written is best, writing indeed is another side of thinking.
Especially since at least once a week my Greek and Roman history teacher in prep school would throw a chalk nub at me and mis-pronounce my name. Chalk, funny. A marker not so much.
I enjoy using chalkboards so much more than whiteboards. Other than the chalk dust, I just can't understand how anyone would prefer whiteboards over chalkboards.
There is much less selection in colors for chalk. And many of them show very poorly on chalkboards. Hagoromo's green for example, is almost impossible to make out on our chalkboards.
The fact that it's still used in many places obviously means it's not unbearable. Besides if you're bothered by the dust you can use the water cleaning methods described in this very thread. It's not perfect, but I would take a chalkboard over a whiteboard anytime.
>Besides if you're bothered by the dust you can use the water cleaning methods
Yes, because I carry large amounts of water around with me for every lecture that I teach. Seriously? The board is covered with dust, the chalk tray is covered with dust and the floor nearby is covered with dust. No one cleans them at my school.
The fix is just to use whiteboards which are just better for everyone who doesn't have a fixation with chalkboards.
This discussion reminded me of my best Diff Eq prof. He would start each lecture by putting a small clock on his podium, and starting at the precise time listed for the start of the lecture. Then he would leap into action, chalk dust flying around him as he explained the subject of the day. He would often go through more than six full-size chalkboards, having a student erase a few chalkboards behind him so he could return to use the first chalkboard when he ran out of room on the sixth one. Then at the precise time scheduled for the end of the lecture, he would take the clock off the podium and leave the room.
You could often see him walking around campus, covered in a fine white dust, looking like a ghost.
It's been 30 years, and I couldn't remember his name, but man do I remember his lectures.
Update: after typing this, I searched for him, and unfortunately found him almost immediately. He just passed away, and there was a memorial to him on the front page of his math department: https://www.math.fsu.edu/DepartmentNews/Articles/Fac_Nolder....
I note this line from the memorial: His students marveled at his ability to draw a perfect circle on the blackboard with a single stroke.
Here's to you, Dr. Nolder!
My crazed DQ Prof was an excitable Russian who worked in a classroom with a chalk board that wrapped around the entire room. He'd start on the right side of the door and end on its left side. Everyone had to rotate their desks during class as he worked his way around.
As a teacher that uses chalk and white boards I can heartily tell you that chalk sucks. It's messy on your hands and cloths, it breaks and is difficult to erase from the board. White board markers are so much nicer. The criticisms of markers seem to be, from the article:
You can't tell when they will run out. This is not true, they fade out not stop suddenly. Also, it is always possible to carry a spare marker or two.
Hand writing is worse with markers. Then look at what you've written and make it better.
White boards deteriorate faster. I currently use white boards that are a sheet of reinforced glass pained white on the reverse face. They've been installed for 10 years and look the same as they the day there were installed.
Permanent markers destroy a whiteboard. The glass boards make it a little bit of work but it instant destruction.
Chalk is less damaging to the environment than marker pens. This is true but can be mitigated with re-fallible pens.
Special "chemicals" are needed to clean a white board. The chemical that I use is water in order to make the cleaning rag damp. The same as I use for chalk.
If you leave writing on a whiteboard too long water won't do the trick and you'll need something stronger, like isoproplanol, or one of the many purpose mixed cleaning sprays
"chemicals" isn't inherently bad of course, if that needs saying. Don't drink the cleaning spray and you'll be fine
My experience was that once you use something more stronger than water, you have to continue using that substance.
Alternately, whatever chemicals are in the marker ink will dissolve previous marks and leave the whiteboard surface intact. Just right over what was written before and it will melt
It's like writing on paper vs writing on a digital tablet. The difference in tactile feedback leads to better handwriting, at least for me.
I'm curious about the phenomenon they mentioned of "circles being smaller with markers". I definitely noticed that when teaching my overall font size decreased on markers vs. chalk, even when using the skinny chalks. But the effective tip size even with small chalk is larger than that of whiteboard markers. So I wonder if we had big ass whiteboards with big ass tips on the markers if the writing style would be more similar. Or if it's more a function of the resistance you get with chalk+chalkboard. Could we make a whiteboard+marker that had more resistance? Like some hall effect or something. Sounds too complex relative to just using chalkboards.
That being said, a downside I didn't see mentioned was chalk dust. I have asthma but still prefer chalk, but I did not appreciate having to pound the dust out of the erasers when I was in grade school. I wonder if they could make the chalk magnetic and have magnetic trap at the bottom or something. But again too complicated.
Any
> Could we make a whiteboard+marker that had more resistance? Like some hall effect or something. Sounds too complex relative to just using chalkboards.
I think that whiteboard vs chalkboard is just personal preference/cultural, and that the explanations in the article are just trying to justify it (which is totally fair IMHO). So I don't think that there's any need to "fix" that problem with whiteboards.
My hand writing is poor and my handwriting with a stylus is worse but screen annotations on zoom have been life changing for me at work. I don’t really care that I cannot write legibly. Quick iteration on diagrams is king.
The german way seems to be a wet sponge followed by a squeegee to wipe off excess water. Here's a masterclass from Frederic Schuller (and a rigorous advanced course in quantum mechanics)
https://youtu.be/GbqA9Xn_iM0?si=Cy7EQOvPtoRqgmhc&t=1070
Pounding the dust out of the erasers was something American students often found fun, especially as elementary school students; this is referenced in the Tom Lehrer song "New Math": https://www.youtube.com/watch?v=UIKGV2cTgqA
Germans also squeegee their blackboards.
In my school, the board was erased many times throughout the day with erasers, and then with water only at the end of the day so it would be "pristine" the next morning.
If you wipe with a sponge, you can't really go on to use it immediately can you? Like you can't write well on a moist chalkboard?
I had a great calculus prof who would wash all the chalkboards halfway through our (3-hour) class, and dismiss all the students for a 10-minute break while the boards dried.
I've had teachers that'd waft a binder at the board while continuing to talk. you can get a decent part of the chalk board dry in under a minute doing that. It's not like you're getting the board soaking wet either. A whiff of water is plenty to clean the board.
Edit: note you can also write on a wet chalkboard just fine. The tactile experience is just a little worse.
Squeegee like sibling comments mentioned, then it doesn't take long to dry.
We used moist chalk to leave stronger duster-resistant marks on the board.
That sounds way better
Wait, you don't use water?! As a German I kind of thought that's normal everywhere, dip the sponge into water, clean the blackboard. Slamming dusty sponges together sounds.. very dusty indeed.
Well, I only ever cleaned them fully in grade school. In undergrad I TA'ed on whiteboard, in grad school it was unfortunately all whiteboards. Except for the rare literal "chalk talk" mini-conferences I was fortunate to attend, where I just erased what I had at the end, no full cleaning. So, I guess I just never "saw how the sausage was made" and implicitly assumed the worst.
Or my grade school never knew better, which is quite possible given its size/location. Or they thought it was funny to make kids deal with all the dust?
Magnetic dust would be worse news if it managed to get breathed in.
Strange question - has the "submitted at" times been edited on this post and all the comments here? I swear I read everything on this submission, including the comments, several days ago, but nothing here is longer than a few hours.
Actually, google search agrees with me - if you search for the title here + hackernews, it says that it saw this post and several of the comments 6 days ago (apologies that I can't link to the cache as this is no longer a feature of Google).
Why are all the post and comment times here saying less than a few hours ago?
It's been second chanced and "shadow time altered" (probably).
You can see from the ID number that this post really is much older than seven hours.( bonus l33tc0d3 qu3est: knock up something to probe and plot posts per unit time, etc. ( I'm taking my dad to the shop instead ) )
* https://news.ycombinator.com/item?id=26998308 * https://news.ycombinator.com/pool
Falsifying timestamps is a kludge that HN uses when moderators give a post a second chance to gain traction on the front page.
(Personally, I have a strong aversion to falsifying public information like this, and I hope that they will prioritize implementing this better.)
This might explain why I see a post, then have trouble finding it the next day. It sounds like it can move around in the order of things.
That might be a different mechanism.
Unlike Reddit, the ordering of HN posts isn't only a function of the numbers of votes, number of comments, and time. Some other moderation activity can cause a front page post to suddenly be buried many pages deep.
I did all my undergrad in ink, and I loved it. Christmas time allowed me to use red and green and brown markers on my tests. The ball point pens had less friction, and I could write faster. Sometimes, an incorrect answer would still get points as I did not "erase" what I had previously written.
> Conrad also pointed out that if one accidentally applies permanent markers on a whiteboard, then the board would be “instantly dead,” a nightmare not applicable to chalkboards.
Not so.
Like dissolves like. You take a dry-erase marker and over-write the permanent, and then wipe both off.
The weirdest thing about chalkboards is the placebo effect they give to doing math.
I can be a blithering idiot talking math to someone without props but in front of a chalkboard I can be the second coming of Galois.
No, whiteboards don’t give the same buff.
Same for the audience!
I started to use water soluble crayons (stabilo woody) for my whiteboards and they are great.
The only small drawback is that you cannot easily correct by erasing with your finger (possible but you need to insist)
Chalk, the Emacs of boards.
I tried extending this analogy to dry erase boards, and all I could come up with was MS Paint
Chalkboards : whiteboards :: Emacs : Visual Studio Code
When I saw the OP's headline I thought "because mathematicians think with chalk the way I think with code". One of the reasons why I Loathe and Detest LLM-based development is because I've developed the (potentially very bad) habit of working through my ideas with (sometimes heavily commented or literate-programmed) code—and LLMs basically take that workflow away from me almost entirely.
One of my math teachers in university always brought with him a dry sponge in a small blue bag. (a lighter sponge that you don't wet before use). Brilliant lecturer.
Someone had described writing with hagoromo chalk to be as smooth as "lipstick on a mirror". I've never tried it but I'd love to.
maybe a wise use of technology?: never adopt a higher complexity tech when a lower one fit well. And white boards are less clear (to me) and markers dry (often in the worst moment). And about slides... very easy for prof, but i cannot copy a slide, always follow the reasoning, so having the things written is best, writing indeed is another side of thinking.
Whiteboards have hugely better contrast for reading.
Chalkboards all day, every day.
Especially since at least once a week my Greek and Roman history teacher in prep school would throw a chalk nub at me and mis-pronounce my name. Chalk, funny. A marker not so much.
Chalk boards are the OG dark mode.
If it ain't broke, don't fix it
Lectures are one of the greatest cargo cults ever. Why people, scientists in particular, are so unscientific?
I enjoy using chalkboards so much more than whiteboards. Other than the chalk dust, I just can't understand how anyone would prefer whiteboards over chalkboards.
Yeah, it's the chalk dust. It's that simple.
Also different colors on whiteboards is occasionally helpful for clarity, e.g. color-coding an equation to a line in a graph. But that's pretty minor.
we had colored chalk for that purpose in my school for math at least
There is much less selection in colors for chalk. And many of them show very poorly on chalkboards. Hagoromo's green for example, is almost impossible to make out on our chalkboards.
I had some teachers allergic to chalk. They sent students to pound the dusters on the balcony.
>Other than the chalk dust,
You know, the worst part that makes them unbearable and a literal health hazard to use.
The fact that it's still used in many places obviously means it's not unbearable. Besides if you're bothered by the dust you can use the water cleaning methods described in this very thread. It's not perfect, but I would take a chalkboard over a whiteboard anytime.
>Besides if you're bothered by the dust you can use the water cleaning methods
Yes, because I carry large amounts of water around with me for every lecture that I teach. Seriously? The board is covered with dust, the chalk tray is covered with dust and the floor nearby is covered with dust. No one cleans them at my school.
The fix is just to use whiteboards which are just better for everyone who doesn't have a fixation with chalkboards.