VideoQuest

Just taped a discussion on the difference between "precision" and "accuracy", with my calc class. I haven't looked at the tape yet, but I fear it's not going to be usable for National Boards-- the situation felt a little contrived (possibly, because this was the first time I had a student, one who's planning to transfer out of the class, do the taping, and other students even said that that was off-putting)-- a big part of that was, I think, that my carefully-crafted set of "focus questions" fell a bit flat: the students said that they weren't sure what I was looking for from them (so, that's a launch problem: I should have focused more on the notion that EVERYTHING is pointing back to the difference between "accuracy" and "precision", and I should have made it clear that there's more than one right answer to each question, so long as you can justify it).

For future use, I'll definitely change my first question (which gives six similar measurements of the same object, and asks "what do you think the actually length of the object is?") to "which OF THESE measurements do you think is most accurate?" Possibly, I'll go back to putting the camera on a shelf (though, that has problems, too...)

A major problem is that I think my materials didn't do a good enough job of emphasizing that it's possible to be BOTH accurate AND precise: the consensus opinion quickly was that there's a sort of exclusive relationship, or at least that "accuracy" is a "rough estimate"... Late in the prompting questions, I asked "Is it possible for something to be both accurate and precise?" Maybe it'd be better to ask "What is an example of a measurement or set of measurements that is both accurate and precise?"

Still, there was a great moment when Sanchez was struggling with the English, and so I encouraged him to use Spanish (after some cajoling, it went much better, and I was able to follow along). I suspect that my mentor will say, "It'd be really great if you could use that..." We'll see how the 15 minutes around it looks.


Anyway, I might re-use this material with my IMP3 classes, too. Maybe even next week, if I can't think of a better time for it.