The 10th grade spent most of this class period watching Selma for their history class, but they came back for the last 20 minutes or so to take a quiz. Here are a couple of interesting snapshots from that assessment.
First, this set of x-t and v-t graphs drawn in a way that I’d never seen before. The matching of the shape for x-t and v-t wasn’t new to me—that’s a common early idea while they are still sorting out what it means to think in the graph language and what graphs really show.
What was new for me was the curling of the graph. I thought it was probably how she was showing the object turning around, but I wanted to know more. These happened to be drawn by one of my advisees, so I felt comfortable grabbing her before we left for the long weekend and asking her to talk me through her thinking. (Since she and I already had a really good relationship, I thought I probably wouldn’t cause her undue anxiety over my fascination with her mistake—she knows I’m 100% on her team and that I’m not worried about her doing well in the end.)
The graph starts off okay (shape-wise—though the numbers don’t quite match the problem). It turns out she was reading “5 m/s for 3 seconds” as “it gets to 5 meters at 3 seconds”. Same for the final part (“it gets to 10 meters at 4 seconds”). The “stops” part doesn’t match that same model for how the graph works, so she has a mash-up in her head with more and less accurate ideas of how to make the graph. For the looped part—she told me that a circle is 360º, so 180º is half of a circle. And you could go under, like she did, or over—either one would work—to show that half circle being made.
That entire combination of ideas—the graph is a picture of the path, the speed as a where-at-what-time, and the correct idea about not moving showing time moving forward but no position change—added up to a really unique set of graphs.
Here’s a different student on a different problem. It’s the image from a TIPERs problem with a problem statement edited to be close to something that was said in class by one of my students last trimester. I was hoping to give them to opportunity to get caught up on that tempting idea (so they would be prompted to address it) and/or give them the opportunity to work on evaluating claims and writing responses (one of the scientific abilities that we’re working on developing).
I chose this response to share because it’s a more unique way of answering it—talking around the idea of slope rather than addressing the slope-is-velocity straight on. It’s also an early argument written by a particularly strong student, and I expect that she will have some really nice responses later in the course based on the arguments she gives during discussions in class. So it’s a little under-developed. I noted to her that it seemed like she was leaving out parts that she was thinking in her head. I was also impressed that she made sure to mention that both objects were going in the same direction—she was trying to make her evidence specific enough to match the point she was trying to make.
Overall, it was a great quiz for them, especially since they were so rushed in taking it at the end of the class period. I can already tell that this group will be yet another one that I’m frustrated to part with at the end of ten weeks. I want to do more with them!