Birds in Space– We started our day off with discussing the forces acting on a bird sitting on a perch. Then someone asked if the bird was on Earth, which lead to a nice comment about a bird not wearing a helmet so that it could breathe. Someone else sent a link to a shutterstock image of a bird wearing a space helmet. I had to include it to remind me (and the students) that saying where everything is happening is important (at least in Ms. Medrano’s class). Here we include the object naming and sign conventions. As the discussion was happening, I was thinking about what we normally do.
Normally, we’d tell students the different types of forces (normal, tension, friction, and force of gravity). Then we would go into type-feeler-dealer notations. I’m thinking if we go into feeler-dealer notations and then creating the need for the type, would that create a better space for students to need to label the forces. I’m thinking that the way I’ve always done it is better (mostly because it’s the way I’ve always done it), but then there could be advantages I don’t yet see with going the way it was presented to us in the workshop.
I do like that the sign conventions were added into the template so that students can decide on a final convention at the end of the whiteboarding session. I also had feelings about the summation of forces, but I didn’t write them down. I’ve inserted images of Kristy’s, Kim’s, Geoff’s, and my group’s boards below so that I can remember what mistakes our students might make. All of the boards are supposed to have some common misconceptions on the board somehow.
Our group chose to focus on the surface and the earth as one thing. I really liked how Yasiri put the question. When we raise the ball above the dirt, what is “pulling it down”? Is it the dirt? Is it the earth’s field? Actually, I’m not sure if she said earth’s field or if I’m inserting some of my own ideas there. I wonder if maybe here, I don’t tell students the types of forces, and they can argue it out a bit. Then we create the need to differentiate the different types. Or would that allow for misconceptions to root itself and then it’ll be hard to undo them? More thinking required here.
Ball, Sand, Fan
For our next activity, we went into whiteboarding our ideas on Ball, Sand, Fan. If my group hadn’t pointed it out, I would not have noticed that the ball’s velocity was also changing. I’m glad Adam and Emma were patient and kind enough with their words to let me know that there was some sort of acceleration for parts of the ball’s motion.
I’m not going to post my notes and pictures here because it’s telling too much. Rather, I’m going to remind myself to look at the CMPF- Day 11 notes that are uploaded into Google Drive. Even now, looking at the notes and screenshots I took, I cannot tell that the ball was speeding up or slowing down. When I went into office hours today (yes, I know…I actually made it to an office hours session), John walked me through the interaction and acceleration directions. I’m pretty sure it came up a few times during our class discussion because I kept writing over and over again: ?- acceleration vs. interaction and confusing acceleration & interaction. I’m guessing it would be here at this point when students recognize balanced and unbalanced forces.
When we drew the summation of the forces, it was easy to see that the forces were balanced (for the part that was balanced). I thought that we would only discuss balanced forces, but now that I’m looking back at my notes, we go into unbalanced as well. Actually, now that I’m really reviewing my notes, the whole programming portion goes into balanced or unbalanced + direction of sum of forces. Insert face palm emoji. (When I taught middle school, I always used to say something along the lines of- we’re just glad you made it to the party. I’ve finally arrived to today’s Pyret party)
Before leaving the Zoom, Melissa showed us a demo of two carts on a cart and showing how the forces are equal and in opposite directions of the graph. I’m thinking this is when we do our Levi’s vs. the tree spring scale discussion. I think adding that demo would reinforce the N3L idea, but then she said she never really calls it N3L. So now, I have to go back and think about it again.
At the end of today, I’m glad I went to office hours AND blogged about the whole experience…because I’m not sure I would have arrived at the same conclusions if I write this tomorrow. Now, time to complete the homework.