Day 64: Kinetic Energy, Exploding Carts, & Volume

December 11, 2018 / Marta R. Stoeckel / 2 Comments

AP Physics 1: Kinetic Energy

I am being compensated by Pivot Interactives as part of their Chemistry Fellows program.

Students used Pivot Interactives to collect data for a relationship between an object’s starting height and its velocity at the bottom of a ramp to work toward a relationship for kinetic energy. Because the activity included directions for how to make each measurement, I got complacent and rushed through the pre-lab discussion, which meant some students were lost on the goal of the activity. I think I would have been better off taking a little more time, and pointing out connections between the directions in the activity and the measurements we discussed.

Physics: Exploding Carts

To start working toward momentum conservation, students launched pairs of carts off each other and plotted the ratio of the masses and the ratio of the velocities. Rather than measuring the velocity, we worked out that since the carts have a pretty constant velocity after the explosion, if they hit the end stops simultaneously, the ratio of the distances is the same as the ratio of the velocities. I like that this forces students to start making some predictions about how they need to adjust the distance, rather than waiting until the end to come up with a model.

Chemistry Essentials: Volume

The Modeling Instruction chemistry curriculum has a lab I really like to show that 1 cm³ = 1 mL, but I’ve struggled to make it work for my students. Both when I’ve used empty geometric solids and a selection of cylinders, doing the math to calculate the volume in cubic centimeters has been a huge hurdle. Today, I tried the lab using plastic cubes that are 1 cm on each side and it finally went smoothly. Students were actually paying attention to the relationship, rather then getting lost in the math to calculate the solid volume.

Day 63: Work, Quiz, & Histogram Interpretation

December 10, 2018 / Marta R. Stoeckel / 1 Comment

AP Physics 1: Work

To introduce work, I had students pull a cart up a ramp to a consistent height, but changing the angle. They then sketched force vs. distance graphs and saw the area was pretty consistent.

Physics: Quiz

We wrapped up Friday’s mistakes whiteboarding, then moved into a quiz on impulse. I’m finding students are loosing track of the different variables we have, which is making it tough to use the equations accurately. I think we might take some time soon to do a “glossary” of all the variables we’ve gotten so far this year to see if having a reference like that helps.

Chemistry Essentials: Histogram Interpretation

To wrap up Friday’s labs on mass and change, I projected some histograms of the class results. The discussion ended up being a lot of me asking a question, followed by one student responding, which is not what I like to go for. I need to spend some time thinking about better prompts I can use on these graphs to get more student-to-student discussion going.

Day 62: Quiz Day, Mistakes Whiteboarding, & Burning

December 7, 2018 / Marta R. Stoeckel / 2 Comments

AP Physics 1: Quiz Day

Students took their unbalanced forces quiz. I included an experimental design problem from the 2016 AP Physics 1 exam but told students I was essentially using it as a pre-test since I haven’t had them try any of that sort of problem yet and want to see how well they are translating what they’ve done in the lab to written problems.

Physics: Mistakes Whiteboarding

Students did some mistakes whiteboarding with yesterday’s problems. I was wary of how it would go in my 6th hour, since I only have eight students and they chose to work in one large group yesterday. There was a lot of great conversation yesterday, but it turns out a lot of students had written down steps without being clear on why they were taking that step, so this was a good opportunity for students to clarify those gaps.

Chemistry Essentials: Burning

Students carried out the experiments they’d planned yesterday to see how mass changes during dissolution. Afterward, they burned steel wool on a balance to get one more example. On Monday, we’ll discuss the results. I collected all of the changes in mass in a spreadsheet to produce class histograms of the results that we’ll also discuss on Monday.

Day 61: Mistakes Whiteboarding, Impulse Problems, & Designing Experiments

December 6, 2018 / Marta R. Stoeckel / 1 Comment

AP Physics 1: Mistakes Whiteboarding

Students did some mistakes whiteboarding with yesterday’s problems. A few students said they feel like unbalanced forces are easier than balanced, which I made sure to point out is a great indicator of how much they’ve grown in using free-body diagrams and vector addition diagrams.

Physics: Impulse Problems

Students worked on some problems using yesterday’s results on impulse. Overall, the problems seemed to go well, but I need to think about how to handle whiteboarding. I’ve got one section of 30, where I’ll be able to handle whiteboarding the way I normally would. My other section is only 8 students, and they ended up gathered around a single table having a lot of great discussion about how to do the problems. I’m not sure how much a whiteboarding session will add to their understanding.

Chemistry Essentials: Designing Experiments

We spent some time talking about the graphs I made of yesterday’s lab results, then moved on to starting the next set of mass and change labs. I asked students to plan their own procedure for finding the change in mass for sugar dissolving in water and Alka-seltzer dissolving in water. This turned out to be harder than I expected, so we ended with some whole-class discussion to figure out what steps we needed and why.

Day 60: Problems, Board Meeting, & Conservation of Mass

December 5, 2018 / Marta R. Stoeckel / 1 Comment

AP Physics 1: Problems

Students worked some unbalanced force problems. The set I gave them is mostly what I call “alphabet soup problems”, were there are only variables, no numbers. My students still get nervous about those problems, but they did very well with them, nonetheless. They are also starting to feel more comfortable relying on diagrams to set up their math, which is fantastic and lead to some great conversations during the problems today.

Physics: Board Meeting

We had our board meeting for yesterday’s impulse lab. The results were the best I’ve seen with this lab to-date, which was great to see. My students this year are more comfortable with the LabQuests than the students I had last year and I spent significantly more time on the pre-lab discussion than I had in the past, and the result was a lot more groups than usual where their slope came convincingly close to the mass of their cart.

Chemistry Essentials: Conservation of Mass

Today students looked at the change in mass in two scenarios, ice melting into water and two liquid solutions getting mixed together. As soon as I started to preview the lab, students started sharing their predictions for what would happen to the mass completely unprompted, so I decided to take a few minutes to let them discuss their predictions. I planned to have students get the initial mass of the ice, then work on mixing solutions together while the ice melted, but it turned out to be challenging for a lot of students to shift between two different experiments. I think it may be better to just use hot plates to help the ice melt so students can do one scenario completely before shifting to the other.

Day 59: Board Meeting, Impulse, & Particle Diagrams

December 4, 2018 / Marta R. Stoeckel / 1 Comment

AP Physics 1: Board Meeting

We had a board meeting for yesterday’s lab on Newton’s 2nd Law. Overall, students got very nice results and were very successful at making sense of what they saw.

Physics

This group added some notation to their graph to find the units on their slope

Physics: Impulse

Students used an elastic string to tie a cart to a force sensor in order to find a relationship between the cart’s change in velocity and the area of the force vs. time graph. I’ve tried this lab a few times without great results, so spent a lot more time on the pre-lab than I had in the past and its looking like results will come out fairly nice.

Chemistry Essentials: Particle Diagrams

Students looked at the change in mass as they spread out a piece of steel wool and started drawing particle diagrams. My co-teacher and I agreed we want to ramp up the graph interpretation in the course, so we made a histogram of the class results and spent a fair amount of time discussing them. Students had some great observations about the graph.

Day 15: SOS Diagrams, Ramp Lab, & Density Representations

September 24, 2018September 24, 2018 / Marta R. Stoeckel / Leave a comment

AP Physics 1: SOS Diagrams

I took a few minutes to introduce SOS diagrams for momentum and impulse, then had students whiteboard some problems. The biggest challenge was thinking through what are useful snapshots to use but, once students wrapped their heads around that, things seemed to go very smoothly.

Physics: Ramp Lab

Students started collecting data to make position vs. time graphs for a cart on a ramp. This was their first time using the tracks and their first time using LabQuests, so it was a lot to take in. Several groups commented the first data point was the hardest to get, but, once they knew what they were doing, the data collection was quick and easy.

ramp lab.jpg

Chemistry Essentials: Density Representations

Today was the density quiz, so we started by using whiteboards to review some different ways to represent density. Most students seem pretty solid on the particle diagrams, but mass vs. volume graphs are challenging for a lot of them. In general, graphs have been challenging for a lot of my chemistry students this year, largely because I overestimated their prior knowledge and haven’t adapted as well as I’d like.

density particle.jpg

Day 14: Board Meeting, Dueling Buggies, & Density Challenge

September 21, 2018 / Marta R. Stoeckel / Leave a comment

AP Physics 1: Board Meeting

We had a board meeting on the impulse lab students have been working on. There were a few groups with really nice results, but this is a very tough one to get consistently accurate slopes, which made the discussion tough, even though my students did a nice job. It was a little tricky getting to the formula we’ll be using for impulse since the lab had a non-constant force, but the equation assumes a constant one. Next year, I might switch to the half-Atwood machine, rather than saving it for unbalanced forces.

Physics: Dueling Buggies

Students finished up the dueling buggies lab practical. I saw a much wider range of approaches than in my AP classes this year; most of my AP students are in the same math classes, which I think encourages them to think about problems in similar ways. My regular classes, meanwhile, have a much wider range of students, so there was a lot of great discussion about different ways to think about this problem.

Chemistry Essentials: Density Challenge

I am receiving access to Pivot Interactives this year in exchange for piloting some of their chemistry activities.

Students used Pivot Interactives to make mass vs. volume graphs to identify unknown liquids by their density. A lot of students had some trouble getting started, but, once I pointed out the similarities to the density of water lab we’d done, they were very successful. The videos don’t zero the balance so that the graph will end up with an intercept; this was the first graph with a non-zero intercept they’ve seen in this class, so it was challenging, but we were able to work through it. I think just about every group picked gallium as their unknown liquid, which is fitting, since it would be the hardest to do in the classroom.

Day 13: Impulse, Dueling Buggies, & Mistakes Whiteboarding

September 20, 2018 / Marta R. Stoeckel / Leave a comment

AP Physics 1: Impulse

Students finished up their data collection for the impulse lab. Some groups have really nice looking data, while other groups have graphs where the pattern is much less clear. I need to spend some time trouble-shooting this lab to see about getting more consistent results. Most of the groups did a nice job of taking turns operating the LabQuest, even without me explicitly directing them to.

Physics: Dueling Buggies

Students wrapped up yesterday’s mistakes whiteboarding, then started work predicting where two buggies would collide. My classes, especially my 1st hour, are taking very quickly to mistakes whiteboarding, so the conversations were much better than I usually expect at this time of year.

Chemistry: Density Mistakes Whiteboarding

We only got through one problem yesterday, so we finished doing mistakes whiteboarding for some density problems. Yesterday, it was very tough to get students to speak up, so today I had students spend a minute or two talking to a neighbor about each whiteboard before we shifted to whole class discussion, which helped a little. The biggest factor was a few students who were gone yesterday were very eager to participate and, once they asked some questions, other students seemed more comfortable speaking up.

Day 12: Impulse & Mistakes Whiteboarding

September 19, 2018 / Marta R. Stoeckel / 2 Comments

AP Physics 1: Impulse

We started by discussing the idea that both the magnitude of a force and the amount of time its applied seem to matter for changes in momentum to get to the idea that we could compare the area of a force vs. time graph to the change in velocity. Students used elastic strings to connect carts to force sensors and started collecting data. This was the first lab where students used the dynamics track and where they collected quantitative data from the LabQuests, but students seemed to get comfortable with the equipment pretty quickly.

Physics: CVPM Mistakes Whiteboarding

Students did mistakes whiteboarding with yesterday’s quantitative CVPM problems. In my 1st hour, a lot of groups were very vocal about picking a mistake one of them had made, and I love the way this places a value on their mistakes and gives them the opportunity to conquer the mistake.

phys mistake.jpg

Chemistry Essentials: Density Mistakes Whiteboarding

This was my chemistry class’s first experience with mistakes whiteboarding. I started the hour with a short vocabulary review that seemed to help cement the key concepts we’re working with. The class was very quiet during the whiteboard presentations, so we only go through one. I think tomorrow I’ll have them do some talking to a neighbor about each board before we shift to whole class.

chem mistake.jpg

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Properties of Matter