using jing for feedback

I just had another example of how to use screencasting to aid in teaching. I had several students emailing me with problems they were having with various software projects and instead of emailing them back with written comments I simply opened their software, turned on Jing (the screencasting software I use) and talked about what I saw regarding identifying and diagnosing their problems. I then uploaded the screencasts to screencast.com and emailed the students back with the link. Very quick and painless!

screencasting in modern physics wrap up

The semester is just about over and I thought I'd post some of the lessons I've learned:

Preparing material

As I've posted before (here here, and here) I'm posting mini-lectures online ahead of time and requiring students to view them along with reading the book before each lecture.

• I found that doing the detailed screencasts before the overview screencast worked the best because I wouldn't repeat myself as much.
• I averaged 4 detail screencasts for each class. Each one is capped (by the software) to five minutes though I rarely used that much time
• I liked that I could really focus and put down exactly what I wanted to say in these. When I compare that to how I used to lecture I would often not consult my notes enough and realized later that I forgot to say things.
• I'm not interrupted with questions and so don't lose track of the important things I'm trying to get across (note that in class all I do is answer questions, see below)
• I could save even more time in class if I posted screencasts with homework hints
• I feel that the solutions sets (I screencast these as well) are much more useful to students as I can say what I really mean. In the past I would write terse descriptions of the equations etc but now, since I'm talking, I can be much more thorough
• I started by posting both the screencasts and the screen-shots of what I was working on (especially when I used my wacom tablet to write notes). However I reasoned that the students would probably learn better if I just put the screencasts up and encouraged them to take their own notes (especially since they could pause the recording to get all the details right). I don't actually think the students did much of this, though

In class

I would tend to go to class with just a list of the questions the students submitted, a four-sided die (to pick which homework problem they need to do as a daily quiz), and a piece of chalk.

• I didn't feel like I needed to prepare much because the screencasts were usually pretty fresh in my head. This tended to work fine because I would really just answer their questions anyways.
• I would answer their questions pretty expansively. What I mean is that I would paint the large picture again to make sure all the students understood the context of all the questions. This enabled me to essentially relecture the material but I skipped all the details except where they were confused.
• For the daily quiz sometimes I would change the numbers around but mostly I just left them alone. The students were split, some did very well almost every day and some, well, didn't. One in particular told me that he wished we had turned homework in instead because the one time they did that he did very well. I asked why that was and he said because he actually worked at all four problems. When I asked why he didn't do that every day he smiled and said that he gambled most of the time.
• We did five "class quizzes" throughout the semester. I would pose a question and they would have 10-15 minutes to put the answer on the board. Then I would ask 4 follow-up questions to random students. As in previous classes it was fun to watch them work through both figuring out the problem and guessing what follow-up questions I might have.

Exams

They did about as well on written tests as in the past but much better on the oral exams. I chalk this up to the ease of studying from screencasts but hopefully their comments from the student evaluations will shed some light on that.

Modern Physics screencasting update again

This week we're having our first exam. The oral part was yesterday and they did very well. The format is the following:

• All 5 (yes, I know, only 5) students take the oral together
• Each student gets 10 minutes to complete a problem on the board.
  • The problems are chosen from homework problems and derivations in the book
  • There are five possible problems so all are done by someone
  • If they get stuck it costs them 5 points (out of a total of 100) to get unstuck by me
• They then answer one follow up question from each of their classmates.
  • In the end they all ask 4 questions worth 5 points each (if I don't like the question, they don't get the points

Each of the problems that they had to do could be found on Blackboard as a screencast. Four were homework problems that were found under the solutions folder and one was the Bohr derivation that I did as a supplemental material screencast when I covered Bohr.

I gather they studied by watching the screencasts because they did very well. Tomorrow is the written test so we'll see how well they're learning using this approach.

Modern Physics screencasting update

This is an update about my use of screencasting in Modern Physics.

The class has now started and things are going well so far. I'm using Jing exclusively for the screencasts but instead of hosting them on screencast.com I'm just posting them to BlackBoard. So far Blackboard isn't complaining about the files sizes (between 0.5 and 5 MB) and hopefully it won't complain about the cumulative total (about 15 MB so far). I like using Bb for several reasons. First I'm worried about running out of room on screencast.com (2GB total) but also because I think I'll reserve that space for screencasts for a more general audience (like my screencast that show how to use my grade page or my summary page that all students use). Second I like how you can control when students have access to the screencasts. Of course I could host the screencasts on a Hamline server and just put in an external link in Bb (that I could control access to) but the students might get lucky and guess the url of other screencasts that I'm trying to control. Third I really like how you can track the viewing by student to know if they're actually making use of the screencasts.

Here's what I'm doing for a given class period. I type up a general outline of the material, careful to skip any details that warrant a separate screencast. I then make any additional screencasts for any details I feel might be confusing from the book. Finally I make a screencast for every homework problem (and make sure they don't have access until after the quiz on the homework given in class).

In class we do a quiz on a randomly selected homework problem (using a four-sided die so that students don't waste time trying to guess which problem I'm going to pick) and then I answer any questions they have about the reading that they've posted on my summaries page (link above). If there's time I answer any further questions and give them hints on how to do the homework problems.

The response from the students so far has been cautious optimism. On the first day when I introduced the basic concept one student said that it seemed like I was putting the responsibility on them to learn. I took that as a positive comment. On the second day all but one had used all the screencasts (the one who hadn't thought he didn't have Bb access) and said they "liked it". I'll continue to get feedback from them and adjust as we move forward.

A feature I'd like to start using is to have students use Jing to post questions to me. They could either use Bb or they could use my grade page to post those. Imagine being able to listen to a student showing where they were having problems in, say, Mathematica rather than getting their notebook and trying to discern their syntax!

Quantum mechanics without imaginary numbers

I've been thinking about how the Schroedinger equation intimidates students because it is inherently complex:

(note the red i). This has led me in the past to say things like "quantum mechanics is weird because apparently the universe is both real and imaginary" and "we can only see the real parts". Now that last quote especially is suspect since what we can "see" is really the magnitude squared of the wavefunction:

which corresponds to the probability density of finding something in a particular location. But I'm coming around to a position where even the first quote above is suspect. It seems to me that you can rewrite the equation as two coupled equations:


Note how the 1's and 2's switch places. What I've done here is renamed the real part of as and the imaginary part of as . Only here I'm just numbering them and not really giving any preference to either. These two equations are totally equivalent to the original equation and what it says about the universe is that for every object you need to keep track of two things. In the end to make predictions about the object you'll need but note that I don't need imaginary numbers at all!

I think interpreting those two equation is of interest as well. Essentially the spatial curvature of one produces temporal changes in the other and vice versa. That's actually pretty cool as you could stare at a snapshot of both the two and predict what's going to happen in the next moment of time.

screencasting software

Well, the news came out last week about Google Video being shut down. I was not exactly happy given my plans for screencasting this coming spring semester. So I've spent the week trying to find some other alternatives. Here I'll put in a few of my findings. TeachTube Teachertube has similar lack of limits to file size and total number of uploads as Google Video. It's optimal resolution is half of Google's (320x240 vs 640x480) but Google actually reduces your videos to 320x240 after some processing anyways. You can mark you files as private and embed videos just like Google too. They have a semi-malfunctioning feature where you can upload support files to go along with the video. Overall it seems like a decent alternative to Google. Btw, the malfunctioning part is that when you click on the support files you're taken to a page with EVERY support file listed. WinFF I don't like the default file size that camstudio produces so I'm starting to use winFF to reduce it by roughly a factor of 2 by converting to .mp4 format from the avi format. The quality once it's on Google seems about the same. Jing Just today I started using Jing on my mac (it works on macs and windoze). It's pretty slick as the screen capture that it does seems to have very small file sizes (3.5MB/minute for full screen) AND they host your screencast for you at screencast.com for free! You get 2GB of space and 2GB/month bandwidth which is pretty good. What I really like about it is how easy it makes everything. You can keep it running in the background and when you make a video the controls are obvious and then when you're done it immediately puts it on screencast.com for you. All with one piece of software! There's also no delay between uploading and being able to view it. Plus they don't do any post-processing to reduce the quality. Of course the biggest downside is the 5 minute limit on videos but I'm willing to work with that! Elluminate Live This is software that Hamline has paid an academic license for. It's actually very slick. I used it yesterday during an interview I was a part of and I was very impressed. It's designed for online courses and I'm planning to use it immediately for my ongoing online course. I really like how you can grant microphone privileges to anyone logged in and how students can "raise their hand". It keeps track of who raised their hand first. Very cool. It also lets you share other windows on your screen so it would work very much like a screen cast. Well, we'll see how it goes this week . . .

Almost two weeks without tv

I don't really miss it. This past weekend there were a couple of times where just vegging in front of it sounded good but I knew there wasn't really anything on. On weeknights I've been busy cleaning the kitchen, brewing my iced tea for the next day, checking the discussion boards for my online class (online quantum mechanics, sounds fun, huh?), reading books, and posting to my blog. The boys are usually in bed by 8 and I go to bed around 10:30 so it's just 2.5 hours to fill. Dexter season 2 came in the mail recently and I am pining for it. I can't decide if that's allowed or not. I suppose I know deep down that it's not but it does sound like fun to watch. At least I wouldn't be watching commercials and I could pause it any time to deal with anything that comes up (I've been getting the evil eye from my wife for not responding to the kids when the tv's on). There's really no single show that I miss. I know Law and Order will always be there for me and things like Hulu.com seem to have the oldies but goodies so I don't feel like I have to watch something the night it premiers. Of course this is all during my j-term at Hamline when all I'm teaching is my online course. Once the spring semester starts I'll probably just use the time to get work done (like grading, the bane of my existence). We'll see.