Day 71: Board Meeting, Practical, & Density Again

AP Physics: Board Meeting

Students whiteboarded their graphs from yesterday’s video. Once I had my 2nd hour find a class average for the slopes of their vertical velocity vs. time graphs, everything fell beautifully into place and there were even gasps when one student sketched a free-body diagram. In my other hour, a lot of groups skipped the directions for making the v-t graph and tried to take shortcuts that didn’t work, so I had to step in a little more. This reinforces my thoughts yesterday that I should have spent some time discussing the midpoint method.

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Physics: Unbalanced Forces Practical

Students started a practical to predict the time it will take a cart to roll down a ramp given the cart’s mass and the ramp angle. For the first time, I had several students ask if I could just do a diagram or calculation for them, so I left the pen I usually carry at my desk and kept my hands in my pockets to avoid encouraging that.

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Chemistry Essentials: Density Misconceptions

Today, I have students blocks of the same material, but different volume, and asked them to determine whether volume affects density. A lot of groups had trouble funding the volume with a ruler, rather than later displacement, so I should have spent a little more time on a pre-lab discussion connecting yesterday’s volume measurements to today’s.

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Day 69: Quizzes Galore

Today is the last day before winter break.

AP Physics & Physics: Quiz & Mystery Tubes

AP quizzed over conservation of energy while regular quizzed on Newton’s Laws in 2D. Afterward, I got out the Mystery Tubes rather than starting a new topic. Students were a little fried since they had tests in just about every class, so I think they appreciated the chance to do something low-stakes after their quiz. My students were definitely loopier than usual, and that lead to some creative models of what’s inside the tubes. Next year, it might be worth putting a lab practical on this day instead of a typical quiz.

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This bug’s name is Todd. He lives inside the tube and moves the ropes.

Chemistry Essentials: Mistakes Game & Quiz

There was only time for one group to present their board yesterday, so we continued the mistakes game today before students took a short quiz on density. The mistakes game was fairly chaotic, but there were also some really good questions. I need to put in some more time working on norms for discussion, but I’m hopeful they will be able to have some good whiteboard discussions.

Day 68: Whiteboarding, Problem Practice, & Whiteboarding

AP Physics: Energy Predictions

Students whiteboarded drafts of their answer to which interaction dissipates a bouncy ball’s energy. One of the things I like about this activity is every group agreed the table is where most of the energy is dissipated, but there was a variety of evidence cited that gave some good opportunities for discussion. Afterward, I showed a thermal video of a weighted tennis ball and we played with the happy/sad balls and seismic accelerator.

Physics: More Problem Practice

Students got some additional practice with unbalanced forces in 2D. It was one more day than I think was truly necessary for their understanding, but confidence has been a big struggle this year and it seemed to help a lot of them feel like they can do the problems.

Chemistry Essentials: Mistakes Game

I did the mistakes game with yesterday’s problems, and it was very rocky. I think it wasn’t ideal timing to introduce whiteboarding since tomorrow is our last day before break and a lot of students are very restless. I’m also really struggling in Chemistry Essentials, more than when I’ve taught it in past years, to get students focused on chemistry during chemistry.

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Day 67: Video Analysis, Speed Dating, & Density

AP Physics: Video Analysis

Students continued working to determine whether a bouncy ball dissipates most of its energy from impact or from air resistance (I’ll have an article about this activity in the January issue of The Science Teacher). Today, students used LoggerPro to analyze the videos they made yesterday and collect evidence. There were a lot of great conversations about connections between energy and motion, which is exactly what I’m after with this activity. Most students had a draft of a CER about where the energy was dissipated by the time they left class.

 

Physics: Speed Dating

As part of my effort to focus on lowering the social stakes in my class, I had students do some whiteboard speed dating to go over yesterday’s goal-less problems. There were a lot of great conversations; the best part was how many students I heard asking “How do you know?”. My 1st hour in particular did a great job of finding and correcting mistakes in each others’ work. I also am continuing to talk about my pedagogical choices more than usual, which seems to be helping students go along with what I’m asking and hold each other accountable for participating. Particularly in my 1st

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The units got fixed on the next rotation, but I forgot to snap a new photo

Chemistry Essentials: Density

We discussed the results of yesterday’s lab to get to a definition of density. I skipped doing a true board meeting because, with break looming, I was worried about time, but students didn’t have as solid a mental model of density as I would have liked when they were working on the worksheet. It was a good reminder that pedagogical shortcuts have their cost.

Day 66: Missing Energy, Goal-Less Problems, & Mass vs. Volume

AP Physics: Missing Energy

Students started working on an activity to determine whether a bouncy ball mostly dissipates energy due to air resistance or due to the impact with a table (I’ll have an article on this activity in the January issue of The Science Teacher). Today, students worked on sketching LOL diagrams and velocity vs. time graphs for each explanation, which lead to some good conversations about the connections between energy and motion. Each group also recorded a video of a bouncy ball that they’ll analyze in LoggerPro tomorrow.

Physics: Goal-Less Problems

Students worked on some goal-less problems for Newton’s 2nd Law in two dimensions. I was very explicit with my students that I use them to make it okay to start a problem without knowing where you are going. We also spent some time discussing key steps students should take (like deciding whether the forces are balanced or unbalanced, drawing and annotating diagrams, etc) which helped a lot of students see where to start.

Chemistry Essentials: Mass vs. Volume

Students worked on finding a relationship between the volume of water and its mass. I had students design their own procedure for the lab and I think they could have used more pre-lab discussion; I usually keep the pre-lab pretty short in favor of doing a lot of coaching lab groups, but the class is bigger than usual this year and I was spread pretty thin, which in turn fed some classroom management issues. I’ll need to keep that in mind for future labs.mass vol.jpg

Day 64: LOL Diagrams, Elevators, & Volume

AP Physics: LOL Diagrams

We did the mistakes game again today (which my AP students now think of as standard whiteboarding in physics) for some problems with conservation of energy calculations. To avoid getting bogged down in the algebra, where most of my students are pretty strong, I had them put their mistake in the LOL diagram or writing the conservation of energy equation. Most groups worked on an accurate solution before they made their mistake, and one group did a nice job of setting up an equation for a problem where 10% of a baseball’s energy is dissipated before it reaches the peak of its path.

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Physics: Elevators

Students whiteboarded their work on Casey Rutherford’s elevator situations worksheet. A lot of students struggled conceptually with the direction of the net force, but seemed to resolve that by the end of the hour. I’m trying to lower the social risk of whiteboarding to get more engagement, so I gave each problem to two different groups, then had them meet and come to a consensus on a solution. Afterward, students did a gallery walk of all the whiteboards. We also discussed a video I made of a balance on an elevator to reinforce the worksheet.

 

Chemistry Essentials: Volume

Students filled geometric solids with water to find a relationship between the volume and the amount of water they could hold. I need to put some thought into how I introduce the lab; in particular, I don’t think my students have much concept of why this relationship is worth looking at. I know I can make use of that as we move into density, but I’m not sure how to frame the lab so they see a purpose in it up front.

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Day 63: Conservation Problems, Board Meeting, & Reaction in a Bag

AP Physics: Conservation Problems

Students started working on solving problems with conservation of energy. There was a fantastic moment when I overheard a student say “I don’t understand number 3 yet; I need to draw my LOL diagram.”

Physics: Board Meeting

Students discussed the results of the 2nd Law lab from earlier this week. I put more pauses into the whole-group discussion than usual for students to talk with their lab groups about some question and was very conscious of asking for claims the group, rather than the individual, had come up with and made explicit those claims were rough drafts. This seemed to ease some of the fears about speaking up.

Chemistry Essentials: Reaction in a Bag

Students reacted calcium chloride, sodium bicarbonate, and bromthymol blue in a Ziploc bag. to see another example of conservation of mass in a reaction that forms a gas. Next time, I might combine this lab with the Alka Seltzer one to make a more involved exploration of whether gas has mass. Aside from this feeling more like a true chemistry lab than the Alka Seltzer one (students definitely connect goggles with “real” chemistry), that may give the opportunity to go into questions such as which was the better method of capturing the gas or whether all or some gasses have mass.

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Day 63: Bar Charts, Board Prep, & Particle Diagrams

AP Physics: Bar Charts

Students whiteboarded yesterday’s problems for the mistakes game. In both my classes, students were generally excited to do the mistakes game and I contributed almost nothing to the discussion, which was fantastic. Afterward, we took a few minutes to use some thermal camera images to see examples of energy dissipated by friction, including a photo I took of my car after driving it.

Physics: Board Prep

I’d planned to have the board meeting today, but we ended up just prepping whiteboards today since enough groups had issues with their data that I think it would have been tough to have a good discussion. I tended to let poor data slide last tri, since it was easy enough to recover during the board meeting, but I think a lot of groups are counting on being “that” group during the discussion. I think having those groups re-do their data collection today helped set the expectation that they shouldn’t plan on being “that” group.

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Chemistry Essentials: Particle Diagrams

Students worked on a worksheet to practice drawing particle diagrams. The students who’ve been engaged in the labs so far were able to breeze through the worksheet and had some good discussions along the way. I’ve got more students than last tri, whoever, who checked out during those activities and had a lot of trouble with the worksheet as a result. I need to think about how I will interrupt the vicious cycle that is starting for those students.

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Day 61: Bar Charts, Mistakes Game, & Burning

AP Physics: Bar Charts

We discussed the results of yesterday’s lab in order to define kinetic energy, then I showed them the derivation for elastic potential energy. Since we’d already defined change in potential energy as the area of a force vs. displacement graph, I think I could have put that derivation on students. Afterward, I introduced students to LOL diagrams and set them to work sketching bar charts.

Physics: Mistakes Game

I love Kelly O’Shea’s mistakes game, but I’ve been having trouble getting my physics students comfortable talking as a whole class, so I decided to try lowering the stakes. I had them prep whiteboards as usual, but then they presented to another group, rather than the whole class. There were a lot of great conversations between groups and students were much more comfortable speaking up. Afterward, I gave students time to do a gallery walk of the post-discussion boards.

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Chemistry Essentials: Burning

Students burned steel wool on a balance to observe the change in mass. Afterward, we used Post-It notes to make histograms of the change in mass from both yesterday’s labs and the burning. Last trimester, I skipped the class histograms, but I think the helped this group to meaningfully interpret their results. I also got excited when a student brought up conservation of mass before I did, which I don’t manage as often as I’d like in this course.

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Day 59: Energy, 3rd Law, & CER

AP Physics: Intro to Energy

Students measured the average force and the displacement required to give a cart the same change in height on several different ramps. They sketched the force vs. displacement graphs, which I used to introduce gravitational potential energy and work.

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Physics: 3rd Law

We ran out of time to hit Newton’s 3rd Law during last tri’s unit on balanced forces, so today we dove in. I showed students a pair of carts, then asked them to draw interaction diagrams and free body diagrams for various collisions, as well as to predict which cart will experience a larger force. One group gave me a hard time about how deadpan I was when they asked if their prediction was right, so we talked a little about Clever Hans the Math Horse.

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Chemistry Essentials: CER

As part of the follow-up on yesterday’s lab, I introduced students to the CER framework. I had students identify the claim and evidence in a car commercial, then come up with some potential reasoning for the evidence before they started a CER on whether the mass of steel wool should change.