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How to draw dotted lines on chalkboards, MIT style (2021)
- rel 4y agoGreat video showing the process of learning the technique https://youtu.be/hbWeSHbL-rM https://youtu.be/hbWeSHbL-rM
- FoomFries 4y agoYep, these videos have been around for some time. Good stuff! https://youtu.be/RqC7QpNrprg https://youtu.be/RqC7QpNrprg
- jkingsman 4y agoThis is SO satisfying to see and hear performed well: https://www.youtube.com/watch?v=l789l6np-qA https://www.youtube.com/watch?v=l789l6np-qA
- implicit 4y agoBe sure to turn the closed captions on!
- isoprophlex 4y agoZdrrrrrrr drrrr drrrrrr zrrrr
- garaetjjte 4y agoThat sound is very unpleasant.
- wyclif 4y agoHe 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/ https://www.glasswhiteboard.com/
- light_hue_1 4y agoYes. 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.
- geenew 4y agoStraying 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)?
- wyclif 4y agoNo, you just have to be careful when installing them or reinstalling/moving them. Make sure it's solidly mounted and there's no problem.
- Sharlin 4y agoIt'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.
- layer8 4y agoThose create a shadow of what you write, because the glass creates a gap between the writing and the white background, right?
- choeger 4y agoI have to ask. Why is it "white"-board vs. "chalk"-board? Back in elementary school, I learned to call the former "black"-board.
- gumby 4y agoNot 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.
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- b112 4y ago"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.
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- rationalist 4y agoI'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.
- b112 4y ago
- khazhoux 4y agoI 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.
- ChuckNorris89 4y ago>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.
- timthorn 4y ago> I remember reading here about the fairytale that is Japanese chalk Specifically Hagoromo chalk, I think
- michaelcampbell 4y agoI 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.
- Grimburger 4y ago> there is one really, really cool thing you can do on chalkboards that you can’t on whiteboards: make dotted lines Seriously?
- baq 4y agoThat was my first reaction. Then I’ve watched this from a sibling comment: https://www.youtube.com/watch?v=l789l6np-qA https://www.youtube.com/watch?v=l789l6np-qA Yeah you can’t do dotted lines on a whiteboard.
- unwind 4y agoI 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.
- enoch2090 4y agoOne 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.
- somat 4y agoChalk 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.
- pantalaimon 4y agoOne 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.
- falcor84 4y agoWhile 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.
- pantalaimon 4y agoOf 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.
- dowakin 4y agoCheck out explanation by Walter Lewin https://www.youtube.com/watch?v=GhawwXcQsUs https://www.youtube.com/watch?v=GhawwXcQsUs
- sslalready 4y agoI 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+dotted https://www.youtube.com/results?search_query=walter+lewin+do...
- jacobkg 4y agoIf I recall correctly, Walter Lewin could also freehand draw perfect circles on the chalkboard
- martin_a 4y agoIn 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.
- pbhjpbhj 4y agoVery 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 https://youtu.be/FBxhkRu9imA using a long springy tool, https://youtu.be/W_P-L0axcqs https://youtu.be/W_P-L0axcqs using a short tool that pivots.
- yreg 4y agoHow is this MIT style? Many people using chalkboards all around the world do this.
- elzbardico 4y agoMIT as an institution is a bit over-self-referencing sometimes.
- 908B64B197 4y agoBecause MIT doesn't know about them, but they know about MIT!
- madcaptenor 4y agoThis 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.
- VSpike 4y agoI 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!
- nickdothutton 4y agoI 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.
- idleproc 4y agoI 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.
- chrisweekly 4y agoIf a picture's worth 1,000 words, here a video would be worth 1,000 pictures.
- knodi123 4y agohttps://www.youtube.com/watch?v=l789l6np-qA https://www.youtube.com/watch?v=l789l6np-qA
- maliker 4y agoI 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.
- Rayhem 4y ago> 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.
- cubefox 4y agoYou can waste ours and hours to something in tikz which could probably be done in 30 minutes with SVG. Sigh.
- anil_gr 4y agoPeople do this all over the world. How come it is MIT style :-)
- ubermonkey 4y agoThe 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.
- typhonic 4y agoI 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.
- layer8 4y agoNowadays that dark mode is in vogue, chalkboards should get a renaissance over whiteboards, right?
- tveita 4y agoI 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.
- xwdv 4y agoI 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.
- rcktmrtn 4y ago> 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.
- TheCondor 4y agoThis 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 https://www.youtube.com/watch?v=eAhfZUZiwSE
- Ccecil 4y agoMy 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.