A lecturer who is speaking and writing on a chalkboard (or equivalent) usually knows the lecture well and is writing to emphasize and explain key points.
A lecturer who is using PowerPoint often does not know the lecture well, and is trying to hide behind the slides or use them as notes to remember what to say.
Both may be experts about the domain they are discussing, but much more often the chalkboard presenter knows the lecture being given.
The best lectures I've seen have powerpoint & chalkboard, sometimes with an overhead projector. Each have their purpose.
1. For displaying text, graphics, animations, etc a powerpoint presentation is great.
2. The chalk board is great for pulling out important equations that will be used throughout the lecture (not lost on slide changes) and to interactively work through a problem. You can draw something out and then ask students what to do next and then execute.
3. Overhead slides are great to manipulations on complex forms. For instance showing how a parser works on a piece of text you can use a pen to mark up the text. Or to show how different actions can effect a system. For instance if we increase the interest rate, the line moves like this etc. This allows you to answer questions in real-time in a visual way.
I see some professors use pen tablet input on computer slides during a lecture. This is similar to what you describe for overhead slides. In practice, they also seem to use it for the things you describe for the chalkboard.
My favorite video lectures are Gilbert Strang teaching Linear Algebra with nothing but a piece of chalk and a whole lot of chalkboards (the kind that slide up and down, revealing other chalkboards underneath). I can't think of any way those lectures could be improved by any sort of technology.
I have met a few people who use Keynote (PowerPoint eqv for OS X) who spend a lot of time refining their slides, animations, and embedded multimedia to get the perfect lecture. I would imagine they would do fine at the chalkboard, but seem to want to be in a "perfect message" kick.
I honestly think this is related to the ideas in Edward Tufte's "Cognitive Style of Power Point: Pitching Out Corrupts Within" [1]. I've had professors who used PP elegantly, but, anecdotally, their methodology was far different. I'd speculate that PP simply doesn't have the information capacity to truly cover complex material.
If a professor understands this, they can use it effectively as a skeleton of a lecture which persists aiding students' intuition of the hierarchy of the material. If a professor, who may well understand the material, doesn't catch the information dearth of PP, they often only end up presenting a small part of the material.
From my experience it really depends on the class that you are taking. If the class relies heavily on images that cannot be easily drawn or represented and needs little textual content to achieve ideas PowerPoint presentations can really work well.
When you have subjects like mathematics and physics purely chalkboard whiteboard lectures is the only thing that works, even classes that are based heavily on either really need a chalkboard.
A mix can work well when the lecturer needs to represent a large amount of diagrams and concepts but still needs to explain how to work out complicated concepts, like example problems. (This is usually where the lecturer really knows a subject.)
I don't believe that Maths or Physics can really be taught using the traditional lecture format. The lecture may suffice to run through the techniques of various proofs, or tell the student what he/she needs to learn. The only way really to learn these technical subjects is to sit down with a pencil and paper and do it through. The same is true for Computing Science. Until you run through the examples and derive/write things for yourself, you'll never truly understand them, regardless of the format of a lecture, or the capability of the teacher.
For what it's worth, I have a degree in Maths, a PhD in Physics and I am develop software for research purposes, when I don't teach - so I have some experience.
The best way for a student to learn these hard technical subjects is for them to sit with their colleagues and go through group exercises, alongside a lot of hard individual work. The teacher's job is merely to help them over the hurdles they have difficulty with, and to show them the things that are truly worth learning. Although I never went through it myself, I suspect that the Oxbridge system of having indiviual tutoring sessions in small groups as the basis of the teaching is probably perfect for these purposes.
The Oxbridge system relies heavily on lectures to set the scene for the group supervisions though. You only get one or two hours of small group tuition per week per topic, so you need to make the most of it. The system generally goes: go to lectures to be introduced to the core concepts in play, have a sheet of 10-20 example questions to work on per week, bring as much of the questions as you can do to your supervision and go through the correct forms. In between we generally worked in peer groups to make sure we had enough to bring to the supervisions in the first place.
Agreed. I teach 60-minute classes using both a chalkboard and 15/20 slides prepared with Latex and Beamer -- http://en.wikipedia.org/wiki/Beamer_(LaTeX) -- which I post on my course page in advance for to the students to print and use in class.
Slides are useful for many reasons (diagrams that need many colors, animations, etc.) and the chalkboard is useful for answering students' questions and giving more examples if needed. I don't think I could teach well without either of them.
First, let me say that there's a huge difference between teaching presentations (presenting material that students will need to use and be tested on later) and idea pitching or research presentations (where you want people to leave with a general idea and a pointer to the material).
My algorithms professor wrote out the whole outline of the presentation, then would do the whole thing on the board as he went. I loved it.
That said, powerpoints have a very worthwhile benefit in that redistribution is trivial. If you're fortunate enough to be in an Operating Systems course where you're writing an operating system, there's a large amount of stuff where details are very important that can get screwed up when twice-transcribed. Something like a powerpoint is invaluable.
I think the best presenters use both powerpoints (for main ideas) and a (chalk|white)board, for actually working through it.
One of my professors likes to print out all of his slides (which can be up to 50 for any given lecture) on transparencies. Then, when he's showing them on the overhead, he'll stand there and underline things, make check marks (while saying "check please"), etc. Draws smiling faces when something good shows up ("now the numbers are already there for the ALU") and frowning faces for problems ("we have to insert a bubble in the pipeline"). In the end, each slide ends up full of lines, boxes, checks, and faces.
I had an excellent prof. who did this with a Tablet PC using PowerPoint's annotation tools. It seemed like a really natural use for a pen-based computer, and made for a good mix of results- nice, readable slides, but with the spontaneity and temporal benefits of a good chalkboard lecture.
I use Tablet PD with Windows Journal. In addition to what you say, other advantages over chalk are the brightness, the colors, and the ability to instantly post the lecture online. Later I transcribe the lectures into text and just copy the illustrations. Plus, I don’t have to deal with chalk on my shoes, pants, and lungs!
I had a professor whose lecture 'notes' where a series of overhead transparencies that were written out by him in wet-erase marker. The thing that frustrated me that most about them is that they were in essay-style. The entire transparency was packed with words, just a huge block of text. No separation of different ideas, no bullet points. The only breaks from the huge blocks of text were when he needed to show a graph.
It really frustrated me because unlike when a professor writes all of that stuff out on the board, he was able to breeze through the material without pause in barely enough time for anyone to write anything down. I was really frustrated at those lectures because I couldn't find a balance between taking notes and actually paying attention to what he was saying in the lecture.
We had the OHP handwritten essay style of lectures as well, primarily in maths, but I seem to recall one computer science topic that stooped that low. We definitely had one pre-prepared essay type, but most of these were lecturers would just freely write on OHP reels instead of the blackboard. I found that a lot worse, due to people trying to write legibly/exaggeratedly on blackboards but writing 'normally' (and totally illegibly) on OHPs. But my sympathies for the overhead essays, I've been there.
On the handwriting note; some of the lectures at UW in bifurcation, chaos and some others were part of the 'UW Engineering Extension' program ( or something similarly named. ) It was really great because only the best professors with the best handwriting got to be on TV. Enrolling in the class on campus was a double bonus because we got access to the video recordings of the classes, the teachers lecture notes, and, of course, got to sit in the room with the professor ( if a matriculated student at the main Seattle campus ) and ask questions to our hearts content. The downside was that if we asked a stupid question, it was beamed to the rest of the world.
I generally find criticisms like this a bit odd. The issue seems less about PowerPoint than it is about how the message/information gets presented and used. It's sort of like blaming the web for websites where companies just cobble together some of the hardcopy content from brochures and newsletters.
Powerpoint is how the information is presented. Her post is all about how using a chalkboard leads to a better presentation of the material and increased focus. I like to teach using the chalkboard or whiteboard, and prefer learning that way as well.
There are some use cases for slides. A picture or graphic too complex to be drawn on the chalkboard. Animating an example (I've seen Steve Jobs use this to good effect). In my lectures I strive for a minimal slideshow, lots of chalkboard examples, and live demos of example code.
I went to a CS theory class this semester which was taught in a computer lab by a teacher drawing notes into Photoshop with a Wacom tablet. I ended up switching into a compilers class, which is taught by a professor writing notes on a blackboard, and I can already tell it will work out so much better. It's surprising, but it seems the old fashioned way is the best way to learn concepts, even in the high tech field of computer science.
I think it's because the professor was off to the side, drawing on a tablet, while we were staring at the screen it was projecting on. It also didn't help that we were in a computer lab, with huge 22 inch iMacs in front of us, making it hard to see the screen and basically impossible to concentrate. When a professor writes on chalkboard, your eyes tend to follow them around the room, rather than staring at what they wrote.
One of the best points for chalk over powerpoint is that it's easy to diverge from the script if you need to. A good teacher adapts to the needs of the student(s). Secondarily to this, chalk allows for a script that is more interactive to begin with (eg, "who can give me an example of an abelian group?" followed by verifying the axioms).
But, while powerpoint may be a fundamentally weaker medium, I think part of the problem is that a lot of people are simply bad at it. Having an optimal presentation requires a lot of attention to things like pacing, and separating content between the powerpoint itself and the delivery. I get the feeling that a lot of people don't look further than content. Hint: if you print your slides and distribute them as notes, they are not optimal for at least one of those purposes[1].
[1] However, optimal slides printed out with room to take notes during a lecture can often be made into optimal notes by a good student.
I vastly prefer handwritten presentations to Powerpoint presentations, but because it's so dynamic.
First, look at content. When you're delivering a Powerpoint presentation and a great side conversation arises, you are pressured to return to the content of your slides before you divert too far. If you don't, then you've lost your visual medium for interacting with your audience. Granted, sometimes it's better to refocus, but it's arrogant to believe you can always anticipate the best direction a conversation can take ahead of time. Anecdotally, my favorite classroom memories of school involve the teacher abandoning plans for the day because students were passionately interested in a side conversation. I'll note that none of those teachers used Powerpoint slides.
Next, there's form. Most subjects are easily broken down by bulleted lists, but that doesn't mean that it's always the most effective way to transmit information to others. Some Powerpointers are talented enough to genereate lots of high-quality picture-based slides, but they're few and far between. I've met some of these talented few, and they're always clearer on a markerboard, because they are able to dynamically change their diagrams as I ask questions and comment.
I realize Powerpoint works better for some scenarios, but if given the choice, I'll choose the guy with the marker in his hand every day of the week
As an avowed chalkboard lecturer, I can totally understand where the OP is coming from, and I can add a few more reasons why chalkboards are better:
1. Non-linearity---it's easy to reconfigure the lecture on the fly if I'm chalking it out on the board.
2. Interactivity---I can ask for and actually use examples from the students when working through something, and I can even ask the students to come up and write something on the board when appropriate.
3. Real estate---In a good classroom, I might have seven or eight times the area of chalkboard as I do projector screen, and I don't need to erase anything until it's all full. That makes it much easier to refer back to earlier points. It also gives everything I wrote a "place", and I can refer back to what I had "over there on that board" sometimes two or three classes later, and if I don't need the precise content (just a general reminder), that's often enough to refresh it in students' minds.
4. Editing---Have you ever been in a PP-based lecture where there were some errors in a formula or graph or equation? (It might be better to ask if you've ever been in one without errors...) These are hard to edit out, and if the slides for students to look at later, how often does the prof correct them first? I had a theory class in grad school that was terrible for this.
One "big" advantage for PP isn't even unique to it: sure, I could post a PDF of my slides for students to read later. You know what I do instead? Snap a photo of the chalkboards after each class and post that.
The only reason to use projected slides IMO is when there is a long formula that students don't have to write down (e.g. it's in the book) that I need to point to, or a particular graph or diagram that needs to be precise. For these things, I stick a PDF of the formula or diagram on the course website, and pull that up during class to talk about it... briefly, before going back to the chalkboard.
On a tangent, Powerpoint is seriously painful for a distance learning class. To be fair, a person standing at a podium or sitting at a desk and talking into the camera is painful too. The lack of movement is a killer. Think "worst TV program I ever had to watch".
I was filling in at a community college for one of the techs who was running the distance learning classroom for a biology lecture. The person teaching it had the camera pointed at his face while he went on in a monotone lecture voice with small breaks of drawing on an overhead. Everyone in the classroom fell asleep. When he called us asking for questions, I had to mute our mikes and wake people up. I taped the lecture, but would have hated to watch it again.
In this day and age, when the slides to so many academic lectures are available for free online, a professor standing in front of a chalkboard in the same room as you seems to give more value for money.
What value do you get from a professor reading his slides to you, versus just downloading them and reading them at your leisure? With the professor at the chalkboard, however, you feel like you are getting more of his thought processes with more spontaneity. And more of a feeling that it is OK and encouraged to stop him with questions, and maybe even diverge from the day's planned lecture on occasion.
I wonder if universities with professors standing in front of chalkboards will start to attract the best students over time.
i once wrote some notes, scanned them, cleaned them up with thresholding and a raster to vector tool, and then added used them as images (sole content) in a powerpoint presentation. it was a lot of work and loses many of the advantages listed in the article, but it did get a lot of positive comments (the audience was fairly academic, however, so most people in the audience grew up with handwritten overhead notes and so found it "familiar" rather than just "weird").
There's also a distraction issue: you can write while the professor writes, and they can't really talk coherently while they're writing. With a presentation, they can start talking while you're still taking notes.
Additionally, having to write out content in longhand slows down the amount of info you can cram into a lecture.
> Additionally, having to write out content in longhand slows down the amount of info you can cram into a lecture.
I'm not sure if you meant that as a positive or a negative, but that was the biggest advantage for me when I had chalk board classes. If you can't write down everything you want to say, your students can't either.
A lecturer who is speaking and writing on a chalkboard (or equivalent) usually knows the lecture well and is writing to emphasize and explain key points.
A lecturer who is using PowerPoint often does not know the lecture well, and is trying to hide behind the slides or use them as notes to remember what to say.
Both may be experts about the domain they are discussing, but much more often the chalkboard presenter knows the lecture being given.