This last post on short movies made by instructors is somewhat similar to the one I did a couple of days ago. That was about a screen capture movie of me writing in digital ink on my Tablet PC along with voice over. Today, I’m still doing screen capture but in his case it is of me using Excel for a little module I’ve made up about Budget Constraints, again with voice over. Since the Excel file itself is also included, the purpose of the movie is a little different than before. For those students who are uncomfortable going directly into Excel and playing with the spreadsheet, they can get the requisite background information by watching the movie first. Indeed, they may not need to watch the whole thing to get the idea.
Many support unites make videos like this to train instructors on software. My unit does this for WebCT Vista and uses RoboDemo from Macromedia for the purpose. In this case I just used the same BB Flashback Express screen capture software for the purpose.
Movies of this sort make a lot of sense if you, the instructor, expect the students to do a lot of their course work inside some application. In this particular case I think Excel is a great way to get students engaged with the theory part of microeconomics, something that most students historically would say is on a par with going to the dentist.
Movie (2.23 MB)
Excel Spreadsheet (38 KB)
Now a mea culpa. The screen area for the movie is much bigger than what I did before and I violated my own rule and delivered a full lecture on this, going almost 5 minutes. The AVI file that I exported from the screen capture turned out to be 260 MB! The screen capture software cranked for 10 or 15 minutes to generate that. The RM file that I made with the free version of RealProducer is compressing the file by more than 100:1. That’s ok for the audio, but for the video piece, that is too much compression. So if you watch the movie you’ll complain that it is blurry, particularly when there are transitions. The right thing to do is to compress it less, so the resulting rm file is say 7MB or 8MB. But you can’t do that with the free version of the RealProducer software. The Pro Version costs $200 and is probably worth every penny if you’re going to be making movies like this on a regular basis. But for this one blog post I thought it an extravagance so I saved some bucks at the expense that your viewing experience is less than ideal. If you want to see the AVI file, email me and I’ll burn a CD for you.
Let me get to the content itself. The representation that you see in Sheet 1 of the workbook, which is what the movie covers, makes a lot of sense to the viewer, I believe. But you will not find it in any textbook on the subject. The representation makes sense because a computer is being used to render it and hence table values can readily change as the student pushes one of the buttons on the right. And displaying values in each cell makes the underlying ideas much more explicit.
But the way Economists teach this stuff they either do the algebra (which in the spreadsheet is implicit in the formulas for the various cells in the table) or they show the graph which is on the spreadsheet called Graphical_Representation. For students who are a little math phobic – a good fraction of the population that takes undergraduate microeconomics, they never really grasp the algebra nor the geometry. I do believe they can grasp the table. One can teach that first and then go the standard way (for those students who will take more economics courses that will rely on the standard way). I think you’ll find students appreciate the course a lot more that way.
Let me turn to a related issues – assessing the students understanding of the content that is in the spreadsheet (and getting them to internalize for themselves what is in the movie). Regular readers of this blog who have followed my various Excel escapades know I have made other spreadsheets where formative assessment is built in and the students iterate back and forth between the assessment and more presentation. I think that dialogic form is very good pedagogically. Unfortunately, it is extremely time consuming to author in that manner.
So let me suggest here a method that is a little less elegant but a lot faster in the authoring and I think can be made to still have benefit for the students. That is to use the quiz engine of the CMS for the authoring of the assessment piece while using the spreadsheet for where the student does the work. Conceptually this is fairly easily to understand. For example, specific questions are asked about the table, given some specific settings of the prices and income, the students calculates these and then copies the results from the spreadsheet and pastes into the quiz, which then evaluates them (on the server) for whether they are correct or not and to give student credit for having done the work.
There is the issue of how to do this screen layout wise, having two serious applications for the student to work on in conjunction. Toggling back and forth between the applications is awkward and probably creates more of a distraction than one wants. So let me suggest this alternative.
I have verified that with a modest screen resolution of 1024 x 768 on a PC and if Excel is set so that all toolbars are closed, then by having a spreadsheet that shows 13 rows with the default height, one takes up a little less than half the available vertical space on the screen. The other half of that space can be reserved for the Quiz in the CMS. Thus both can show at the same time and the student can readily move back and forth between applications. That means the designer must make both the spreadsheet content and the quiz questions with full awareness of the vertical space limitations. But I think that is quite do-able and a reasonable result can be produced. Using fill in the blank question types in the CMS, the designer can producer fairly rich content and still get the benefits of machine evaluation.
For a large class instructor, this would seem to be an attractive approach.