Posted at Sep 08/2018 11:14AM by Stu 9:
To build off your second point Stu 4, Bill actually says meters several times instead of feet, further adding to your point that he is not paying particularly close attention to the units and therefore the quantities. Also, I think he could have contextualize the rate of feet per second for Ann better. Since he used 45 miles per hour initially, he could have said that is about 66 feet per second. Thus, I completely agree with your third point as well.

I also agree that I am viewing these videos from my own understanding and framework, and therefore bias. Unfortunately, my initial reaction was to find all of the "bad" in the video, instead of also focusing on what is done well. My wife commented on this when I was telling her about the assignment.

Posted at Sep 08/2018 11:50AM by Stu 4:
Good point, Stu 9. I just watched the second video, and Bill is making obvious attempts to address several of the things (units, etc.) that I addressed in my initial comment. But even in the second video, I still see Bill resorting to describing the procedure (e.g. multiply/divide) instead of actually developing the underlying concept.

I am impressed with how many different ways he tries to approach this topic in the last 10-15 minutes of the video, but it was painful to watch by the end. Ann was totally disengaged and it was pretty obvious to me that she felt she was playing "guess what's in my head" with the teacher.

Posted at Sep 08/2018 04:04PM by Stu 6:
Is it the units that matter? Or is it the fact that he doesn't discuss how one quantity is changing with respect to another? The relationship and concept of rate. I don't think including units would necessarily create that connection for Ann.

I agree, there is lots of "guess what's in my head" in both videos. -- I call it teacher bingo because it's bingo when you get it right. -- And he is often leading and answering questions for her. She doesn't get the opportunity to fully express what she is thinking.

Posted at Sep 08/2018 04:45PM by Stu 4:
I agree that the most important thing is how one quantity is changing with respect to the other. After rereading the transcripts, I do think I need to revise my argument some. I think the units are important, but think it is a symptom of a larger problem you're talking about.

Posted at Sep 10/2018 09:56AM by Stu 3:
I don’t think San is thinking of two variables (possible not about varying quantities at all). She appears only to be thinking about counting chunks of distance. I think Bill recognized this (this the two number lines) but I don’t think the numberlines were doing anything but confusing her. She seemed very frustrated at that point.

She clearly has a procedure for finding time given rate, and seems frustrated not to have one for the ‘time type’.

I think her confusion about the units are part of the issue. She isn’t thinking of rate as a ration of two quantities. I think she is thinking about it only as a distance (and the number of chunks of distance give the number of minutes). Focusing on the units might have helped her address her confusion. Certainly be imprecise with them wasn’t helping.