The Minnesota teacher union has our convention on this week, so we only had school Monday through Wednesday. I think staff and students alike are feeling pretty run down, so this is good timing for everyone to take a break.
Physics: CAPM Practical
This week, students worked on the “catch the loot” lab practical for constant acceleration. After how smoothly paper and pencil problems went last week, I expected the practical to go very smoothly, but students really struggled. I also found a lot of groups were not interested in testing their calculation with the materials. I think I underestimated how difficult it is for my students to draw connections between what happens in the lab and what happens on paper. I teach all of my physics sections in the morning, so when my colleague who teaches physics in the afternoon saw how challenging the practical was, he added a brief whiteboarding activity to help bridge the paper and pencil problems to the practical, which seemed to really help his classes. Going forward, I need to make sure I plan how I will help students make better connections between what happens in the lab and what happens on paper.
Students also had their quiz over constant acceleration calculations this week and many of my students were really worried after having their confidence shaken by the lab practical. On the quiz day, I took the first half of the class to have students whiteboard a word problem, which they were able to nail with minimal help from me and seemed to really improve the tone of the class before the quiz. I shared my reasoning for doing that problem, and a student made sure to tell me how much she appreciated that I am paying attention to where they are at and trying to adjust to what they need, which was a good reminder that talking about my reasoning for instructional decisions can do a lot to help students feel less frustrated in my classroom.
AP Physics 1: Balanced Forces Lab Practical
Students did a lot of practice with applying math to vector addition diagrams, including a lab practical to find an unknown mass. My students were quick to recognize the math that would be useful, but weren’t always comfortable with how to use the math. I really appreciated the small class size I have in AP since I think that has helped the class feel more cohesive, which has meant students are very comfortable asking each other for help and very willing to patiently work with their peers when asked for help. The small class size has also made it easier for me to step in before students start to experience any serious frustration and has helped me build trust with my students that I will be able to coach them through things if needed. Knowing the positive impact the strong relationships students have with each other and have with me, I need to keep thinking about how I can do a better job of building relationships in my much larger physics classes.
Physics started constant acceleration this week. We used video analysis to get position vs. time and velocity vs. time graphs for a cart on a ramp, then worked on Kelly O’Shea’s CAPM card sort. This was my first time using video analysis to introduce constant acceleration, and I’m really happy with the results overall.
The big thing I’m thinking about right now is when students are in groups. The first week of school, students were almost timid and weren’t engaging with each other, but tended to stay at their tables, which made it easy for me to pull the full group in when I came to answer a question. Over the past few weeks, things have shifted in a few of my classes. Students are still not engaging much with their groups, but are also leaving their group to go see their friends, which is making it harder for me to gather the whole group when I’m answering a question. I think a lot of it is students are out of practice working with each other after last year and simply aren’t seeing value in staying with their group. I think I need to make much more use of group roles and spend much more time working with students on how to interact with each other and building community so students feel like they can connect with more people in the class.
I think these issues have been compounded by the fact that I have larger class sizes than usual, so I’m juggling 10 groups in each of my classes. That means that if I’m having meaningful conversations with each group, it can be a while between my visits to a given group. I’m realizing that many of my students don’t feel like there is much they can do besides wait for me when they are stuck, which I think is contributing to some of the behavior I’m seeing. I think part of what I need to address is helping students recognize the strategies they have to work through moments of confusion or challenge.
AP Physics: Forces
We started the week with the catch the loot practical, which is one of my favorites since it is a challenging calculation at this point in the year, but so satisfying. This class is only 12 students, so I’ve had a much easier time building a positive class culture and helping students with strategies for when they are stuck. One thing I loved is when the first group finished, they decided each of them should join one of the other groups to help their classmates with the lab practical.
We shifted into forces with some mallet ball followed by Brian Frank’s interaction stations. So far this year, I’ve been really intentional that when we show the shortcomings of a common preconception, I also ask students about what reasonable thinking might lead a person to that idea and explicitly validating that thinking. My goal is to make it so that adopting a new idea doesn’t mean you are wrong or don’t understand physics, it just means you didn’t have all of the information when you formulated your old idea. I saw some payoff with the mallet ball as my students were quicker than usual to let go of the idea that they needed to keep tapping the bowling ball to keep it moving with a constant velocity and talking about the useful aspects of that idea even once they’d adopted a new one. We’ll see next week how that carries over into drawing free-body diagrams.
This week, both of my classes spent a lot of time working problems to practice translating between different representations of constant velocity. In Physics, velocity vs. time graphs seemed to either click immediately for students, or to be a big struggle. Usually, I have a lot more students with an experience somewhere in between. Regardless, by the end of the week even the students who found velocity vs. time graphs really challenging were getting the hang of them. In my AP Physics 1 class, most students seemed to be in a place where the velocity vs. time graphs were clicking pretty quickly.
AP Physics 1 also was able to do the dueling buggies lab practical. We had some great conversation about the sources of uncertainty in their predictions. Each group took a different approach, but got the same predictions for where the collision would happen, which is always fantastic. I’m also starting to see more of my students’ personalities in this class, which is making this class a lot of fun. AP is a lot smaller than my Physics classes, so I’m not surprised that is starting to feel like a cohesive class sooner than Physics.
This week, I also had a lot more conversations than usual with students who said they “aren’t a science person” or “aren’t good at science”. I suspect some of it is rooted in all the challenges of what science classes looked like last year, but that doesn’t make it any less important for me to address. I’ve been slow to start discussions of what skills groups needed to complete a task, but I need to make sure I’m making time for those. I also found myself telling students if their answers were right a lot more than usual in order to help them get some immediate confidence to keep them moving forward on problems, but the downside is it really limits the discussion students have once one of them knows they have the right answer. I need to figure out how I’m going to balance the need to keep the door open for student discussion with how I’m going to help students feel more confident in my classroom.
We had a four-day student week for a professional development day on Friday.
AP Physics 1: Waves
This week week we worked on developing and using the wave equation, as well as a few other concepts on mechanical waves. We started with a standing wave lab in Pivot Interactives. On a few labs this year, students haven’t taken the time to get good quality data, which has made it tough to make sense of the slopes during the board meeting. As students are getting better at constructing new ideas from lab results, they are starting to really see the value in having good results to discuss and this lab was a place I saw it really pay off. Students worked through linearizing their graphs and figuring out units of their slope with very little intervention from me partly because they knew those steps would help their sense-making and partly because they are getting more skilled and need less support. Every group had beautiful data for the board meeting and, as we worked on problems later in the week, I heard a lot of students referring back to their graphs or their qualitative observations to think through a problem. All around, this was a really fun week to watch and listen to my students.
Physics: Momentum Transfer Practical
Students worked on applying conservation of momentum to problems, including a lab practical. For the practical, students had to determine an unknown mass using photogates and a dynamics track. The groups that were able to sketch momentum bar charts that matched the collision they decided to do were typically able to find their mass pretty quickly, but a lot of students struggled to connect their bar charts to what was happening on their lab table. As we move into energy, I need to think about how I’m going to make sure students are connecting representations like bar charts to things they can observe or interact with in the lab and beyond. I did enjoy seeing the different approaches groups took to the practical. One based their approach on cart explosion lab and added mass to their empty cart until both carts had the same velocity after the explosion.
This week, students worked on applying conservation of energy. We wrapped it up with a lab practical to find the spring constant of a popper toy. To help with what makes a good procedure, I had groups start by writing out the steps they were going to follow on a whiteboard. Then, they traded whiteboards with another group and had to follow the procedure they were given to actually collect data. One group came up with a nice strategy of writing out the equation they’d use in their calculations, then checking off each variable as they added a step to measure it.
Physics: Pushing Boxes
Students spent a lot of time this week on problems applying Newton’s 3rd Law and synthesizing Newton’s Laws, including some great problems originally from Matt Greenwolfe where students draw free-body diagrams and velocity vs. time graphs for boxes pushed across various floors. While there was some great discussion, I think these problems would have been more valuable much earlier in the forces model. In general, I think Newton’s 3rd Law feels like an afterthought in how we approach forces. With some shifts in what we’re doing early in this model, we could better integrate key elements of this model and reduce the need for doing some kind of synthesis at this point in the unit.
This was another short week. Parent-teacher conferences were on Thursday night, so Friday was scheduled as a professional development day.
AP Physics 1: Newton’s 3rd Law
This week our focus was on Newton’s 3rd Law. Students predicted which cart would experience a larger force during various collisions, which we then tested using a pair of carts with force sensors and hoop springs. In my grad class this semester, we’ve been doing a lot of talking about the ways language students use can mask meaningful understanding, which got me thinking about how I can make better use of students’ predictions. This year, I tried being very explicit that our task was to find the useful ideas in students’ predictions and to translate those useful ideas into the language physicists use. There was a great moment where a student said “So the force and the result of the force are different things, but we were treating them as the same”, which I couldn’t have planned better.
I also took a page from Brian Frank this week and used some magnetic hooks for an easy setup of a static forces lab practical.
Physics: Newton’s 1st Law
This week was about developing the idea of a force and Newton’s 1st Law using interaction stations and the bowling ball lab. A few students were resistant to actually trying the bowling ball lab this year, rather than actually testing whether what they expected worked, so I had to push some groups to really explore getting the bowling ball moving with a constant speed. Once they got started, however, there was some great discussion.
This was a three-day week since public schools closed on Thursday and Friday for the state teachers union conference.
AP Physics 1: Vector Addition Diagrams
Students started the week by doing Kelly O’Shea’s forces representations card sort. I used the card sort to introduce vector addition diagrams, and students easily recognized key aspects of the VAD. The rest of the week, we worked on applying VADs to solve problems. They are successfully applying the VADs, but aren’t feeling confident in their skills just yet.
Physics: CAPM Practical
After wrapping up some problems using the constant acceleration model, students started working on a practical to figure out where to start a marble on a ramp so that it lands in a passing buggy. We ran out of time for students to test their calculations. While students made good progress, many are uncertain of their skills; I’m hoping that completing the practical on Monday will help them build confidence.
To wrap up constant acceleration calculations, we worked on some problems out of the College Board’s workbook. There was a lot of great discussion as students worked through the relatively complex problems. Students have been nervous about the early registration date for the exam this year, and working the problems seemed to help alleviate some of their fears.
Students also worked through an activity based on Brian Frank’s interaction stations to start building their model of a force. I had a sub that day, so afterward had students use a reading to define the major types of forces we’ll be using in class and connect them to the stations. We’ll be discussing the stations early next week and I’m thinking about how I want to approach the discussion. This week, I happened to read a chapter from Bryan Brown’s Science in the City where he talks about how teachers often miss how accurate students’ preconceptions are because students aren’t ready to express those ideas in scientific terms. I’m wondering how I might change the way I usually approach this discussion (and many others) to do a better job of recognizing and building on what students knowledge, regardless of the language they use to express it.
Physics: Constant Velocity Problems
Students worked problems, including the dueling buggies practical, using the constant velocity of a particle model. On their weekly reflection, a lot of students wrote about navigating different ideas within their groups about how to complete the lab practical. I was really excited to see that multiple approaches were suggested in most groups and that students were thoughtful about how to balance making everyone heard with moving forward as a group.
We also did some mistakes whiteboarding. In both my courses, I’ve been pleasantly surprised by how quickly students are buying in to this activity. My Physics students have been pretty quiet during the whole-class discussions, but they are consistently referencing it in reflections as something they find helpful for learning and where they feel proud of their work in class.
AP Physics 1: Constant Acceleration Representations
We spent this week working on getting representations for constant acceleration down. I made quite a bit of use of Brian Frank’s magnetic vector manipulatives during class discussions of motion maps. I think it would be worthwhile to make a set for each lab group; I don’t have magnetic surfaces at my lab stations, but I think the laminated arrows would still be useful to students while they’re working.
I’ve been doing more work on collaboration so far this year, and I’m seeing it pay off with students seeking out input from a greater variety of people when they’re stuck and with ideas jumping between groups much more than in the past. I especially love when students start working problems with one group, then whiteboard with different people and begin by comparing approaches.
Physics: Constant Velocity Calculations
Students worked on applying the constant velocity of a particle model to calculations, including predicting where two buggies will collide. One challenge, which has come up the past few years, is a lot of students are having trouble connecting the calculations to the representations we’ve been using. I think there’s a couple of things going on. In a lot of classes, once students have taken an assessment, they no longer need to use those skills, so I think some students feel like they are done with constant velocity representations after last week’s quiz. I think the other hurdle is some students, especially those less confident in math, are looking for things they can memorize to bypass the sense-making involved in sketching the diagrams. I haven’t figured out good strategies to help students work through these hurdles aside from coaching individuals and small groups on doing the sense-making and sketching the diagrams when they are stuck. I also need to keep reminding myself that as the year goes on, more will get on board with continuing to use skills we’ve assessed and working through the sense-making steps.
Final project proposals are due tomorrow, so students worked on finalizing their topic. I got to have a lot of fun conversations today to help students narrow down their topic. One student had picked out a clip from The Cat in the Hat but wasn’t sure what she wanted to do with it, so we spent some time talking about the physics involved.
Physics: Curved Mirror Board Meeting
We whiteboarded the results of yesterday’s lab to get to the mirror equation.
Chemistry Essentials: Activity Series Practical
Students got a pre-1982 penny and a post-1982 penny, each with a wedge cut to expose the insides, and used an activity series to predict which would react with hydrochloric acid.