Sliding into Fall

Oops, it did it again…. The Fall term 2011 has managed to sneak up on me, like its 2010 predecessor. All of a sudden, it’s all back. I am facing a crowd of 400+ students, teaching the same introductory physics class I taught last year, in the same humongous, with its microphone, its two big screens and no white board.

This year I am doing things differently, though. The main change is that I am using presentation software (obviously Keynote) to deliver my lectures, something that at the beginning of my teaching career, back in 1996, I had sworn to myself never to do [0]. How did that come about ?
Last year I was confronted for the first time ever with the task of lecturing in this large room, which has no white (or black) board. It has two big projection screens, hooked to two computers (of course one can use one’s own portable computer). Furthermore, there are two document cameras [these are essentially good ol’ overhead projectors, except that they allow one to write on a regular sheet of paper, and have the writing projected on the screen(s)].

Next best thing
I did not even for a moment think of using slides. I have always had the (preconceived) idea that for introductory physics and math courses, it is very important that students not be fed pre-digested notions, presented in some bullet format. I was convinced of the importance of seeing concepts slowly take shape on a board (black or white), as instructors work their way through the various logical steps, using the simple and precise language of algebra. To me, the fact that the instructor needs some time to write things down seemed beneficial, in that it gives students a few seconds to “chew” on each equation, sentence, definition, passage.
While I still think that there is some general validity to that, I have to admit that I had until now no personal experience with anything different for an introductory level course, either as a student or as an instructor.
So, since no white board is there, I decided that I would try and duplicate (to the extent that that is possible) the white board experience, by using the document cameras. I would lecture writing on a sheet of paper, projecting it on the screen — it seemed like the next best thing to having an actual white board.

A disaster ?
No. It went OK… I guess.
I got through the semester, and students seemed reasonably satisfied (my student evaluations were actually the best I have ever had for a course at that level) — still, I was not happy with my delivery. Halfway through the term it was clear to me that that is not the way to go.
The problem is, plainly and simply, even though one wishes to use a document camera as if it were a white board, it is not a white board.
One needs to write large enough, so that everyone in the audience will see, in turn greatly limiting the amount of text or equations that can fit on a single sheet. During a typical 75-minute class, I would easily go through 10-12 sheets, and that causes fragmentation in the way information is presented. I soon came to regard that as detrimental to an effective delivery.
What is worse, even though I typically had an initial “plan” for what every one of my sheets would look like, that plan often changed, either in response to questions or requests from students (e.g., to review a problem discussed in the previous lecture), or simply because, as I was lecturing, I changed my mind. I believe that anyone who has taught, knows what I am referring to. An instructor can almost always sense from the audience, whether a particular way to illustrate a given concept, which (s)he thought would be effective, is actually working or not.
If one is using a white board, that is not really a huge problem. There is plenty of space, one can erase and start over, and written stuff “sits” before the students for a long time. Erasing and starting over when one is writing on sheets of paper is problematic. If the plan is altered, if the order in which things are presented changes, then often times one has to start on a new sheet just at the time when a crucial piece of information (an equation, a formula, a concept) is put down. Although there are two projectors, and therefore the last sheet can be left up for a while, I found the whole routine impractical and unwieldy. I would often have to interrupt and dig out previous sheets, on the request of students.
A month ago, when it dawned on me that the beginning of the semester was around the corner, and that I would be teaching the same course, I decided that this year I would try something different.

Better than I thought… so far
The advantages are obvious. First of all, each slide is much clearer, cleaner, better organized. Everything that needs to be stated is there, no risk of forgetting anything important, even if I lose my train of thoughts, or just have a bad day. I can avoid all algebraic mistakes by making sure I have everything right in the first place, ahead of time [2].
One potential problem could have been the fact that screens are mounted too high for the instructor to be able to use a stick conveniently, and the room is too large for a laser pointer to be seen by everyone — plus, there are two screens. On the document camera I could highlight things as I wrote, but how would I be able to point to important stuff on the screen, quickly and easily ?

Have I mentioned before how awesome the iPad is ?
I swear, this device is just a life saver. Yes, I am using it to deliver my lectures. Besides being of course much more convenient and easier to carry around and to use (touch screen technology just works for me), it has added built-in features that no ordinary laptop computer (that I know of) can match. One that is proving crucial to me is the simulated laser pointer, to where I gently press on the screen of my iPad with my finger, on the place in the slide where I want to point and … voilà , a big, fat red dot magically appears on the screen, right where I want it. No, how cool is that, really ?

When it comes to the iPad, all I can do is repeat what I have stated in the past, namely that it amazes me that such a product did not become available ten, fifteen years earlier. I know that they are already selling millions of them, but I am thinking that it will be a big hit especially among educators, as people realize its full potential.

Problems ?
Yes, there are still some.

Making slides is a challenge. First of all, making slides, any kind thereof, is always a lot of work, no question about it. I would be a liar (I mean, even more than I am already) if I denied that the thought of being able to re-use the material in the future makes it less unpalatable. But, it is a lot of work — mostly because the software is… well, it is not a matter of it being bad, as much as it is of it just not being there.
The key aspect to keep in mind is: this is not like giving a seminar, nor a public lecture. One cannot assume any kind of prior knowledge on the part of the audience, and one needs to convey precise, detailed, quantitative information. As I wrote last year, a lot of these students are not comfortable with algebra as they should be, and it is therefore necessary to show in detail how formulae are derived and utilized.
If anyone is aware of software that allows one to write easily equations and animate them (yes, I wrote “animate” — as in, e.g., move something from denominator to numerator, simplify etc., as if I were doing it on the white board), I would greatly appreciate a pointer.
It is not that one cannot accomplish the task using regular presentation software, it is just slow and inefficient (imagine having to construct fractions and square roots by putting lines together, creating objects and placing them around… many, many times) [3]. And, most software created to embed equations into presentations created with commercial software such as PowerPoint or Keynote, is either impractical or does not deliver [4].

Also, technology is good but not quite perfect yet. It is not possible to project on two screens two different slides. Why would I want to do that ? Well, I would like to keep the last slide on one screen as I go through the next one. I can do that but it is clumsy, I have to connect one of the two screens to one of the two built-in computers and project the same presentation (saved in PDF format somewhere) in parallel, so that I am one slide behind. Yes, it is as clumsy as it reads, and one in two times I forget to advance the other presentation, and students have to remind me (I suppose it keeps them awake).

Another thing that requires some initial adjustment is the delivery. If one need not write, one can go faster — much faster. It is important that one time oneself properly, or one may easily end up going too fast (not that that happened to me. Students totally did not ask me if I could slow down and/or what the heck I am on).
Another issue on which I can use some advice is the following: again, because I can insert more text into my slides, text that I would not have the time to write in if I were using a white board or my sheets, I thought it might be helpful to add some explanatory sentences here and there. However, that is turning out to be a double-edged sword, because a lot of students try copying slides in their entirety, and the more is written on the slides, the harder it is for them. Of course, to me a slide is not meant to be copied, and yes, I have explained it to them — plus, I am putting my PDF slides online anyway… but, they still asked me to write less on the slides. I guess I am going to have to find the “sweet spot”, hopefully soon.

As far as the rest is concerned, well, computerized homework is awesome — but expensive. I have to admit it, the notion of charging students for submitting their homework assignments is one with which I am not entirely comfortable, even though alternatives are worse (if you are about to suggest that University step in and subsidize that cost, I see stand-up comedy in your future). I think it is high time some Mountain View-based software company step into the education arena…


[0] I mean for an introductory undergraduate physics course. I have used slides before to teach graduate courses, but that is really a different kind of animal.

[1] The room is simply too big. Those sitting far in the back could not possibly see anything written on a white or black board.

[2] Yes, of course I also do that when I lecture on the white board, but confusion, oversights and mistakes are always possible — it is part of being human.

[3] It is true that there are some compatibility and rendering issues when transferring a Keynote presentation from a Mac to the iPad, but they seem fairly minor to me (No, I do not create the actual presentation on the iPad — I do not think that that is quite doable, honestly).

[4] Before anyone passes me this link — I am familiar with that product. The thing is, I could not care less if equations are created elegantly and rapidly — IF fonts are a) inconsistent with those of the presentation software and b) not easily changeable, the software that created said equations, whose purported goal is precisely to make equations seamlessly embeddable into one’s presentation, is useless. Period.

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22 Responses to “Sliding into Fall”

  1. Ian B Says:

    In my experience almost all text on slides is unnecessary and distracting. Keep the slides simple with the exact point or equation you want to illustrate. The online supplement notes can and should contain a bit more, since you’re not there presenting the slides to them. The books Presentation Zen and Slideology are great explanations of how to wield the unwieldy slideshow presentation.

  2. pika Says:

    In terms of writing equations, I’ve a trick that I use for preparing papers that have to be produced in Word. I hate Word equation editor and so I bypass using it by typesetting all my formulas in LaTeX. I produce a pdf from LaTeX and then select and copy each formula as an image from Adobe Reader. The final step is to insert the formula again as an image into a Word document.

    Perhaps you could do the same in Powerpoint/Keynote? I imagine you could prepare your derivation in LaTeX, then grab each line of derivation as a separate image object. Then insert them into ppt and produce an animation, so that each line appears separately.

    • Massimo Says:

      Unfortunately no, that won’t work either because the fonts in LaTeX are different from those in Word/PowerPoint/Keynote, and I do not know of any easy way to change them…

      • pika Says:

        Yes, but if you select and copy from a LaTeX-generated pdf as an image, then you don’t need any fonts, because it’s an *image* you are inserting into Word/Powerpoint. You could have an extra step that you copy the selection from pdf into Photoshop or some other image software, save as jpg and then import jpg into Word/Powerpoint. No need for fonts then. 🙂

      • Massimo Says:

        Unless I am missing something here, I think I understand what you are saying. The problem is, the equation that I paste (as an image, I understand that) into the presentation will look different, font-wise. For example, look at the letter “v” in Word and LaTeX (and the fonts are supposedly “Times-Roman” in both cases)…

      • pika Says:

        What I am saying is that if you produce an image out of an equation, then the “v” that you have will be a set of black pixels in between white pixels in a jpg. No font needed to reproduce that – same as if you take a digital photo and import it into word/ppt, you don’t need any fonts for that. The point of this whole process is that it is a conversion between a vector representation of an equation (with fonts) into a raster representation (a jpg image), which in word/ppt is treated as a photo. 🙂

        And then what I suggested above for showing derivation step wise is that you produce a series of equation “photos”, put them in ppt and animate them, so that you emulate writing each step of derivation by only displaying each next “photo” on the click of the mouse.

      • Massimo Says:

        And what I am saying is that if I do what you are suggesting, which is what I normally do when preparing slides for seminars, it will look like this.

        When I put it up, students are bound to ask “excuse me, what letter is that in the equation ? Is that the same as “v” ? “…

      • pika Says:

        Ah, ok, sorry, I see the problem now…
        Well, then I guess it won’t work in this context.

      • Massimo Says:

        Exactly, and actually it will never work, period.
        This is a huge flaw with LaTeXit, which is specifically designed to create embeddable equations for applications like PowerPoint, or Keynote (unlike LaTeX). Unless there is an easy way to change fonts, one which I have not found thus far, I cannot believe that they did not think of this, which nullifies their entire effort.
        The thing is, most of us use these applications to create slides for seminars, where font inconsistencies are not really an issue, but when it comes to teaching it is a different story.

      • El Charro Says:

        If the only issue you have with LaTEXit is that the fonts are not compatible and students will get confused with the two “v” in your example, why not just paste an image of the letter from LaTEXit into the text? Instead of the one “v”, you insert an image of LaTEXit in between the other words.

        That ought to solve the problem, or am I missing something?

      • Massimo Says:

        Well, it does solve it and in fact I have tried to do it but it is clumsier than making equations by hand — or, at least I go faster that way

  3. Goranka Says:

    Electronic homework: I use Moodle (free software) for uploading students PDFs and online tests etc.

    As owner of a new iPad, I would like to ask how do you connect iPad with the projectors in your classroom ?

    • Massimo Says:

      You need to buy a VGA adapter, if you look at the second photo carefully you can sorta kinda see the cable with the connector at the end…

      As for Moodle: it does not do anywhere near as much as MasteringPhysics, it does not provide you with a rich problem data bank, automatic grading, etc. At least, it did not the last time I checked… maybe it has improved.

      • DundeePhysics Says:

        Isn’t there a problem with MasteringPhysics, with students being able to find online solutions? A problem with textbooks of course as well!

        For your typesetting problems, I think Mathtype integrates well with stuff like powerpoint, but not, I think, with Keynote. It’s not free though. I used this last year for a series of powerpoint slides (often equation heavy) and found it worked very well – made typing stuff in much quicker. I think you can fiddle with the font settings too.

      • Massimo Says:

        I am sure that if one is looking for online solutions one can find them, but as you note, it is no different with MP than if you just assign problems from the book. Moreover, MP allows you to randomize input data, making each student work on a slightly different version of the same problem. While it is not a definitive solution, at least it makes it more complicated than just getting a number from someone else.

  4. Devin Says:

    One alternative might be to do the entire presentation in LaTeX. There are a couple of packages that make it a relatively painless process. (I’m on my phone right now, so I don’t have any links, sorry)

  5. DundeePhysics Says:

    I use (and like) Mastering Physics, for the reasons you outline. My only major issue is that when students do cheat it is very difficult to prove using the online system. With a written answer it’s far easier to see if they have copied material. However the shear amount of time it takes to mark written scripts is immense, so I suspect I’ll be sticking with MP for a while yet.

    • Massimo Says:

      Well, look, my bottom-line is, those who are wanting to cheat are going to cheat, and there is nothing you or I can (or have the time to) do. I think it is more reasonable to think in terms of likelihood of them doing it, or fraction thereof who do. Apparently the creator of MP have addressed this issue, and in a publication in Phys. Rev. ST they argue that cheating is less common with MP (you can find it at the MP web site I think). As for being able to tell if cheating has occurred with written assignments, I really do not believe that that is true in the vast majority of cases. The fact is, aside from the large number of papers that one has to mark, which renders it virtually impossible to spot suspicious similarities, look, there are not many different ways of solving a problem. If two students make the same mistake, you may have a way of arguing that there may have been contamination (and even there in my experience it gets very sticky), but most of the time the solution is correct — what are you going to tell them in those cases ? You both got it right in the same way, and therefore one of the two must have copied from the other ? And if so, who ? I am very reluctant to walk down that path. Students cheat first and foremost because it works, they risk nothing.

      Three years ago I had a student walk in my office with his midterm exam (held a month earlier), which he claimed he had not been able to find until then, because there was a “huge pile of marked papers” and his had been “buried in there somewhere” (except that every other student did find his/hers, and therefore the only one sitting there for a month in that “huge pile” would have been his). He handed it to me, claiming that I had mismarked it, because his solutions seemed correct to him (solutions had been posted online for a month). He handed me his pencil-written midterm, with obvious evidence of someone (him, of course) having erased what had been originally written on the sheet, and replaced it with amended text, manifestly copied verbatim from solutions posted online. I reported that. The university’s position was that I could not really “prove” any wrongdoing… I am taking MasteringPhysics any day.

  6. r Says:

    I have found SMART Board technology to be awesome for math/physics.

    The software is free, works for both Windows and Mac (maybe Linux too…), and it is powerful. <— doesn't really do it justice – equation manipulation using the touch pad is pretty amazing.

    For a big class, you would get the most benefit by using a special projector and a tablet pad – I think about $2000 together, which might be deemed OK for outfitting a room like that pictured. For smaller classrooms, you could use the SMART display board (a giant touch screen), but it costs…I think $3500 for a full system. Not budget busters, but these things will probably have to wait until the coffers are a little healthier. Don't quote me on the numbers, they are word of mouth, but it gives an idea (the first generation outfits WERE $15k-$20, about 9 years ago).

    Also, a touch screen, projector, laptop, tablet pad, video camera, microscope camera, and document camera can all be integrated (unfortunately, ipad/iphone not supported – yet); there is also a multi-tablet system that you could use to let, say, a half-dozen students simultaneously write so as to appear on the touchscreen/overhead (OK for smaller classes). I saw a biology lesson with full technology integration, and it looked like something out of science fiction. I've seen it used like Keynote/powerpoint too, except with a more nimble interface for algebraic manipulations, and instant graphing.

    These systems are being adopted by Ontario high schools in a massive way – my local boards have one such system in almost every classroom. Grade 1 to grade 12. A lot of hardware and expense, to be sure.

    But the killer app is the software, IMO, and you can try it out for free. The math tools are not free (demo version can be tried for free though). Huge downside on hardware cost though…


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