I forgot to take pictures during class today, so words will have to do.

Physical Science: PhET Energy Conservation

After going over the definitions students worked on Friday, we went back to the PhET skate park simulation to look more specifically at energy conservation. I had several different scenarios where I asked students to predict what the energy bar charts would look like for key positions of the skater. The plan was for students to then check each of their predictions using the simulation, but very few groups got to that point thanks to assorted tech issues. I overheard some great conversations where students were really digging into the definitions of the different types of energy along with the details of the skater’s motion to not only make predictions, but find evidence to make supporting arguments. Since it can be tricky to get computer access, I’m planning to project the simulation tomorrow to test the predictions as a class.

Physics: Intro to Motion Maps

Today students added motion maps to their representations of the constant velocity model and practiced translating between representations using the motion detector lab from the Modeling Instruction materials. Once they got rolling, most of my students seemed to get comfortable with this new representation pretty quickly. I think I drove a few of them a little nuts, though. Inevitably, students came up to me to ask if their answers were right and, rather than just saying yes or no, I tried to stick to asking questions about their representations. My goal during class is always to get students to think harder than me (at least about the physics), so I want to get them to analyze any work they aren’t confident about, even if their answer is already perfect. The trick is they’re used to only being asked to think about their wrong answers, so as soon as I started questioning a lot of students panicked and assumed they were way off. I started prefacing each conversation with a reminder that I was asking questions because I wanted to understand their thinking, not necessarily because their result was wrong. That little reminder seemed to help a lot of students to focus on what I was asking rather than immediately start searching for their mistake, which I think made the conversations more valuable even when their was a mistake for the student to find. I’m sure that as students get used to being asked to explain their thinking (and I get better at probing for their reasoning), the instinct to panic and start searching for the error will fade.