I had a great conversation with a fellow small-Minnesota-school-physics-professor today that I wanted to store here so I don’t lose it. He was asking about how my students use screencasts to turn in assessments, and he specifically wondered whether he could make use of the document camera in the lab room to help facilitate that.
I wanted to know a little more, so I asked whether he was thinking that the doc cam would capture their work (from a blank page), or whether it would be used for a static image of their finished work. This got us talking about what would be best from an assessment point of view.
I shared with him that I much prefer to see a page with all the students completed work on it, and to have them walk me through it, adding in all kinds of observations about how they came to each point. I also shared that I don’t overly look forward to the screencasts that start as blank screens. It seems that they’re tedious, sometimes, and I find that I fast forward, often, until I can see where they’re going.
We talked about whether that was lazyness on my part or whether there was something to having students complete their thoughts before we are given a window into their process. I shared that watching students go down blind alleys is useful, if only to count how often they do it. But, in the end, I want to know if they’ve found the right (or one right) path.
He pointed out that he starts from scratch often when demonstrating how to solve certain types of problems. Sometimes this is in class, in front of the students, and sometimes its via some form of screencast. We talked a little about Ken Heller’s research contrasting novice and expert problem solvers. Basically, I figure that we don’t make nearly as many mistakes, and when we do, we often see a teaching opportunity.
What do you think? If you had all the time in the world, would you like to be a fly on the wall watching a student start from scratch when solving a new problem? Or would you get all the assessment information you’d need by letting them futz around, then produce a clean document, and then walk you through it? Some of this reminds me, by the way, of the great talk that Joss Ives gave at AAPT about giving his students time to think during oral exams.
Another thought I had is related to what I just got back from. I play in the Hamline student Jazz Ensemble and tonight we sight-read a piece by Oliver Nelson. Here’s what it’s supposed to sound like:
Trust me, not only did we not sound like that, but I don’t think you would have learned much about our eventual potential as a band by hearing what we did tonight.
SuperFly Physics 
Hi Andy,
Now that you mention it, I wish that students would just start with all of their work on the page. I hadn’t been requiring that on my screencasts, but I would enjoy watching them a lot more if they did.
That said, I do not really know which is better for the student. I hope someone has some evidence on which helps students learn more.
Bret
I know there are a lot of PER researchers who video tape students approaching a problem from scratch, so I would guess there’s some good research out there about this.
Hi Andy, I really like
“…watching students go down blind alleys is useful, if only to count how often they do it. But, in the end, I want to know if they’ve found the right (or one right) path.”
If one is trying to do some research on student understanding of X or documenting common student difficulties, I think that those blind alleys can be informative. But they often have enough trouble discussing why their correct solution works that those blind alleys are generally not useful from an assessment perspective.
Also, I will have to keep in mind that the screencasts go more smoothly from our perspective when not starting with the blank screen.
Hey Joss, see my comment to Bret above. Can you point us to any of that research that shows the effectiveness of watching the blind alleys?
I don’t know of any research that specifically looks at students following the wrong paths, but there are certainly a large number of people that have done research on problem solving that used either individuals doing talk-aloud interviews or video of groups solving the problems. In general, I would say that the blind alleys are considered productive (like the Angry Birds thing of initially shooting a bunch of birds to get the feedback so that you can then develop a proper strategy for the level).
The cases where I would expect that the specific blind alleys are most informative is if they coincide with (forgive me) misconceptions that still show up in many students final solutions. Then those blind alleys can be very illuminating in terms of the student thinking and understanding that is going on in a way that only the final incorrect solution might not be.
All of that being said, I have not personally done any research on student understanding of x, but have done work coding for productive behaviours in group problem-solving activities so that has to be taken into account in what I say above.
Perhaps a middle ground would be to have the document in pen so that all the work is written down and the student has to lead you throught the mistakes too.
There is a difference in what you are getting out of the assignment when you watch the entire process as opposed to a rehash. The talking method with a final write-up helps a student clarify the method, whereas the method of watching the entire process is more designed for the teacher to see the problems that are occurring.
Yeah, I agree with that, which is why I consider myself a little lazy when I talk about preferring the finished product.
As for your “in pen” idea, I think that’s a really cool idea, though I know my students true scratch work tends to happen on other pages.
Very interesting question. For assessment of individual understanding, I prefer to see something that is well laid out, because students have to tell a coherent story about their work and their logic. It’s painful to watch a student slowly work their way to an answer via many wrong turns, particularly because often in those situations I am not convinced the student fully understands how he or she got to the answer that they did. However, seeing the wrong turns can be valuable, which is why I like to use whiteboarding during class time. Then I can watch as pairs of students start with a blank slate and stumble around as they try to solve problems. If I see several pairs stumbling down the same blind paths, I can talk with the class as a whole about those wrong turns.
that’s a great point about the whiteboards, Melissa. I really like how, in class, you can see from far away whether people are on productive paths, and you can intervene when they’re really off course.
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