Energy Theater

At the summer Modeling Instruction workshops in Columbus, we are often lucky to have prominent physics education researchers visit us and speak to our workshop participants. On Wednesday, Dr. Stamatis Vokos of Seattle Pacific University joined us and he completely owned the crowd. I might be a bit biased, as I was really jazzed about his presentation of the Energy Theater.

Using work done by the Energy Project, a research group focused on discovering best practices regarding the teaching of energy in science, Dr. Vokos shared with us a new way to think about energy transfers and transformations. Dubbed the Energy Theater, this representation allows the students to act out the energy transformations and transfers in a system with each student representing a single unit of energy. There is an article in the May 2014 issue of The Physics Teacher that gives a good overview and provides an in-depth look at how to use the Energy Theater in the classroom. I’m only going to share our experiences, so be sure to check out the article.

As it was shared with us, there are four rules to the Energy Theater.

  1. Each student represents a single unit of energy.
  2. Objects correspond to areas that have been marked off on the floor (likely by tape).
  3. Each student represents their form of energy with hand signs.
  4. As energy transfers and transforms among objects, students move to different areas of the floor and change their hand signs.

We were given the example of a cup resting on a hand. The cup is being raised at a constant speed. We chose the person, surrounding air and the cup to be the system. In a modeling classroom, we have tools like energy pie graphs or bar charts that would let us model the problem like this:

piecharts

The great thing about energy pie graphs and bar charts is that they let students show how the types of energy present in a system are transforming from moment to moment. However, they don’t really let students consider how the energy is transferring between parts of the system. For instance, where is that thermal energy? Is it in the cup? The person?

Using the Energy Theater, our group identified the objects in our system and marked off areas on the ground to represent them. We did our work outside, so we used the blocks of concrete and split them up as shown below.

Screen Shot 2014-06-12 at 7.16.41 PM

Next, we decided as a group on hand signs to represent each energy type. While you can use simple hand signals, I wanted signs that involved more of our body to make them obvious. We came up with the following:

  • Kinetic – a simple sideways-V formed by spreading the index and middle fingers
  • Gravitational Potential – both hands on our head
  • Thermal – fanning our faces
  • Chemical – both hands on our belly

This is where the physics comes in. We had to work out as a group how many units of energy were in each object AND in each form. Our location reveals where the energy is while our hand signal reveals what form the unit of energy has taken. We had to reason out how the units of energy should move within the system and how they should change as they did so. The result is a glorious ballet of physics teachers having way too much fun.

As you can see, we (as students) really needed to think through how the energy transformations of the very simple act of a cup being raised at constant velocity. How much thermal energy is in the body? How much transfers to the air? Do we ever run out of chemical energy?

As we concluded our work on that problem, Dr. Vokos asked us to try the case where the cup is being lowered. At first, this seems like a simple reversal of the previous Energy Theater. We quickly realized though that things were different.

See how much fun you can have at a Modeling Workshop?

Reasons I Like This

  • Energy transfers are explicit. Students sometimes have trouble connecting the states of a system. While the O of the LOL charts (a.k.a. energy bar charts) can show energy moving into or out of the system, it doesn’t allow students to show how energy moves within the system.
  • It’s another representation to add to the energy model. Modeling is about finding multiple, consistent ways to represent the same phenomenon and this leads to better learning.
  • This feels like the “Walking Out a Motion Graph” activity in which students model a position or velocity vs. time graph using their own bodies and a motion detector. I like those active representations.
  • It is scalable. If you don’t have room, students can draw the areas for objects on a whiteboard and move multi-sided blocks from area to area. Think of a six-sided die with the faces each representing a type of energy. Check out the Physics Teacher article for a good picture of this.
  • It fits well with pie graphs and bar charts. At any moment, the number of blocks of energy and their types can be determined, so the rest of the class could construct pie graphs and bar charts as students perform the Energy Theater. You could even create a stop-motion Energy Theater.
  • Thermal energy transformations become very apparent here. We quickly realized how much of the energy being used must be transforming into thermal energy.

Concerns

  • Energy as a substance. According to Dr. Vokos, this representation requires students to think of energy as “an immaterial substance”. This makes me uneasy. Will this confuse students? Energy isn’t a substance, but then again, forces aren’t arrows. And we already represent energy as blocks in energy bar graphs. Is it okay to use this model to help them understand energy transfers?
  • Tracking of info. With so many people moving and switching hand signs, it will be hard for students to track all changes at once while the Energy Theater is occurring. I think this can be alleviated by filming it for review or moving through it multiple times and stopping the performers at key moments to assess the current state of the system.
  • Disengaged students. Notice the guy in the green shirt in the videos (me). I picked a role that required me to do very little. In the first video, I chose to be a unit of kinetic energy in the cup which never changes. In the second case, I was a unit of chemical energy in the body that never transformed. In both cases, I was assigned my role and then could have chosen to ignore everyone else. Yes, this is more of a classroom management issue, but with so many students at once, I’ll need to keep an eye on it.
  • The gravitational field. Since using the modeling materials, I’ve taken to explaining that gravitational potential energy does not reside in the cup, but in the cup-Earth system. My students quickly take to this and it sets them up well for AP physics when we discuss conservative forces and fields. How to represent this cup-Earth system in the Energy Theater? Perhaps breaking one area into two smaller ones? Dr. Vokos was kind enough to speak with me at length about this. His suggestion was to place the energy in the cup initially. Use that as your first model. Next, change the mass of the cup. Make it more and more massive and look at how the Energy Theater changes. What would happen if the cup were as big as the Earth? In other words, use the Energy Theater to build towards a revision to your model of gravitational potential energy that requires this new cup-Earth thing to be included. Ultimately, you could even move towards including the field.

There are numerous extensions to this activity. A teacher could easily assign new and different situations for students to investigate or slightly alter the existing state of the system. You might make stop motion videos of the Energy Theater alongside energy bar graphs. This new representation for energy transformations and transfers had me really excited, but I want to think this through before I bring it into my classroom. If you have thoughts of your own about this, I’d love to hear them.

Model Building on Spring Break

My school started its two-week Spring Break this past Monday. My honors physics classes have finished up the mechanical modeling materials (with the exception of the central force model). When we return from break, they will begin an investigation of light and optics. I didn’t want them to spend the next two weeks ignoring physics nor did I want them reading chapters from a book. To keep them engaged and thinking about the world around them, I gave them the following assignment. This is a great group of students this year, so I think our first day back will be very interesting.

We have spent months together not only learning about the natural world, but also learning how to learn about it. In our time together, we have developed models explaining the behavior of pendulums, objects moving with constant or changing velocity, projectiles, balanced and unbalanced forces and the conservation of two quantities (momentum & energy). The tools we have used include diagrams, graphs, mathematical equations and verbal descriptions. At this point, I want to give you a chance to strike out on your own.

When we return from Spring Break, we will be spending our time investigating the nature of light. What is it? How does it move? How does sight work? This study will include things like shadows, mirrors and lenses. We’ll look at the difference between colored light and the white light we receive from the Sun. In preparation for this study, I want you to spend some time during Spring Break doing one thing:

Develop a model for light or a light-related phenomenon.

What is a “light-related phenomenon”? Consider the following questions:

  • If shadows are blocking the Sun, why isn’t a shadow black? Why is it a diffuse gray?
  • Why is my reflection in a spoon upside-down on one side and right side up on the other?
  • Why is the sky red at sunrise and sunset, but blue during the day?
  • If you look at a green shirt under a red light, is it still green? What does this say about the nature of color?
  • Why does the portion of a drinking straw submerged in water seem larger or even broken from the portion still in air?
  • Can you ever add light from two sources together to produce darkness? Or do they always produce a brighter light?

During Spring Break, take time to look around you. Light is ubiquitous, yet to this point we may only understand its nature in a rudimentary sense. Make observations. Draw diagrams. Take pictures or video. If you choose to make measurements, record them. Write down your thoughts. Don’t daydream about light. Purposefully direct your attention to an observation about it. What do you notice? Alter the situation and see how things change. This will be challenging, but you are capable of doing challenging things.

When you return from break, we’ll spend some time together sharing what we found.  

Modelpalooza 2014

Here in Ohio, we have a very robust and active community of modeling teachers. Each year, under the careful direction of Drs. Kathy Harper and Ted Clark, we offer three different workshops (physics, chemistry and advanced) in Columbus as well as three follow-up weekend events throughout the rest of the year. The final follow-up of the school year is Modelpalooza, a day that brings together recent workshop graduates with experienced modelers from around the state. Often, experts in the field, such as David Hestenes, will come and present a talk, and in the afternoon, the advanced workshop graduates present the modeling units that they worked together to develop.

This year’s Modelpalooza was yesterday, March 1st. It remains one of those amazing professional development opportunities where I continue to learn and be exposed to new ideas despite having used modeling instruction for the past six years. We begin the day by sharing modeling success stories. This is important for the recent workshop graduates, as it not only gives them a chance to hear from experienced modelers, but also to share and acknowledge the transformations that they’ve seen in their classrooms over the past six months.

Rather than a national speaker for this year’s Modelpalooza, we decided to take advantage of the wealth of experience right here in Ohio. Experienced modelers presented break-out sessions in the morning to share their own work. We had sessions on CASTLE Electricity by Holly McTernan, Adjusting Modeling for Different Student Abilities by Joe Griffith and ??? (Apologies mystery presenter) and Standards Based Grading and Modeling by myself. I had really wanted to see Holly’s CASTLE session, as I have no direct experience with the CASTLE materials, but my own session went pretty well. The crowd had heard of SBG, but were all relatively new to it. Primarily, the presentation was a walk-through of my own adoption of SBG and what the transition was like in my modeling-based physics classes. A few folks asked for my presentation, so I’m putting a link to it below.

Standards Based Grading & Modeling Presentation – Modelpalooza 2014

The highlight of the day for me though was Dr. Harper’s presentation during the second breakout session. While Dr. Clark was presenting on PhET Simulations in the Chemistry Classroom, Dr. Harper shared a review of the literature on Expert-Novice Comparison in Problem Solving and Alternate Problem Types. I had tweeted some of the research based conclusions that most surprised me. For those folks that were asking follow up questions, I’ve included the literature review handout below. The conclusions that stood out to me were the following:

  1. Transferring math skills into physics is more difficult than transferring them into any other area. This is the Bassok & Holyoak paper below. Does this seem counter intuitive to anyone else? I would have assumed that physics (arguably the most mathematical of the sciences) would allow for a natural flow of knowledge/skill from one domain to the other. I haven’t had time to get a hold of the paper yet, but I plan to.
  2. Students plug numbers into physics problems to free up memory slots. Cognitive research shows that most people have about seven working memory slots in which to hold a piece of information for short term retrieval. Now take a look at one of the introductory kinematics equations - \vec{x}= \vec{x}_{0}+\vec{v}_{0}\Delta t+\frac{1}{2}\vec{a}\Delta t^2. If we consider only every variable a different piece of information, there are five symbols to interpret and keep track of. Your less mathematically adept students will have even more as they work to recall delta means “change in”, etc. By substituting numerical values into the equation early, students are able to lighten their cognitive load so that they can use it for other tasks. Dr. Harper suggests that we don’t push students to solve algebraically too early in their physics courses. Show them the power of it, keep revisiting it, and work them towards this skill once they have a stronger conceptual understanding. If I recall, this is the Sweller paper.
  3. If a problem takes a high school student more than 12 minutes to solve, they think it is impossible. I believe this is the Larkin paper. We’ve all had this experience with our students, but having a hard and fast number that I can tell my students to watch out for will make it easier for me to help them develop good problem solving habits.

The afternoon sessions consisted of the advanced workshop participants presenting on their work from the previous summer. This year we had groups working on circuits for physical science, a really cool equilibrium model for chemistry, and a rates of change model using wine glasses. I am always impressed by the level of thought and work that the presenters have put into their units. We always recommend modelers take that second year workshop, as it helps you move beyond the initial modeling curriculum provided in the first year.

With Modelpalooza 2014 behind us, we move into prepping for the next round of summer workshops. You can find out more about the workshops over at the AMTA website.

Standards-Based Grading: NCGE Presentation

Tomorrow, my colleagues and I will be presenting a session at the National Conference on Girls’ Education. Our session is titled “Bet on the Yet! Promoting a Growth Mindset” and it consists of four of us taking about 15 minutes to discuss methods we have developed within our classrooms that promote growth mindsets among our students. I’ll be discussing standards-based grading which I feel has had a sizable effect on how my students view themselves as learners. This is a version of the presentation we gave at the 21st Century Athenas Symposium through the Center for Research on Girls at Laurel School.

Rather than printing numerous copies of the one-sheet to hand out, I’m posting the handout here. Hopefully folks from the NCGE conference that want to start researching SBG will give it a look, as it contains links to a number of great resources that informed my adoption and use of standards-based grading. In time, I hope to include posts about working through the adoption of SBG and the versions I’ve gone through.

The Tao of Modeling

Today was our first full day of the workshop and things are off to a great start. First, we have a great group of teachers (24 in all) enrolled in the first year physics workshop. Even with the torrential downpour that we started the day with, each of them showed up eager and ready to begin. I’ve mentioned this in earlier posts about the workshops, but spending three weeks with a group of people who want to learn how to get better at their job is invigorating. It energizes you. And this time is even better, because I get to help them learn how to do that. Teaching teachers turns out to be really cool.

After paper work, introductions and FCIs, we got down to business and walked the participants through the ball bounce lab as a way to introduce model building. They did a good job as students – sometimes too good of a job – and kept the discussion moving along. They were a bit overwhelmed and had questions about all the things that everyone new to modeling has questions about: time, classroom management, textbooks, etc. My co-leader and I ended the day with some extra time in teacher mode to address their questions. As we fielded each one, I began to realize that I was responding with the same question I use on my students…”I don’t know. What do you think?”.

See, modeling is not a set curriculum, like say a textbook might be. It’s a framework or skeleton that can be used to build any scientific curriculum. How each teacher constructs that curricula differs according to their personality and classroom needs. There are a number of ways to guide students in the development and deployment of new models. For instance, I don’t use the ball bounce lab in my class while my co-leader does. He grades deployment labs while I’ve moved away from that. Whiteboarding might involve every group’s board going up for discussion or we might put all the boards up at once to look at patterns. There are as many ways to implement modeling instruction as there are teachers that practice it.

That’s one of the big lessons that I hope the participants take away from the workshop. Success as a modeler means finding your individual way…your path…your Tao. It means knowing your students and what the technique and tone for asking them questions is, because I know you have to question them, but I can’t know your kids. It means finding what is important to your class as the time crunch starts to force you to drop topics, because every modeler has had to (since meaningful reflection takes time), but we don’t know what standardized testing you face or what your principal will challenge you on. And it means deciding how to give your kids feedback, because I know you have to, but I don’t know how tightly you, your kids or their parents cling to grades. All I can do is share my way and hope it provides some insight to the teachers that will be trying this for the first time.*

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* – Contrast this with the highly scripted, one-size-fits all explicit direct instruction (EDI) methodology that seems to be the newest form of pseudoteaching.

Modeling Workshop: Behind the Curtain

I’ve been using modeling instructional methods for the past five years in my physics classes. My first experience was in a one-day teaser workshop, which I followed up with the full first year mechanics workshop. A few years later, I returned for the second year advanced workshop which focuses on teaching you how to take the modeling framework and use it to develop your own materials. Now, two years after that, I’m back again, only this time, I’m co-leading a mechanics workshop in Columbus, OH.

The idea of introducing a room full of my colleagues to modeling instruction and teaching them how to use it in their classrooms is intimidating and exciting at the same time. Tomorrow is the first day of the workshop and it primarily involves introductions, the distribution of materials and paperwork, but we may have time to start on the ball bounce intro lab. Our plan for the next three weeks looks something like this:

  • Intro Modeling Units (Ball Bounce and Pendulum)
  • Constant Velocity Model (Buggy Investigation and Game of Chicken)
  • Constant Acceleration Model (Cart on Ramp and Police Chase)
  • Balanced Force Model (Hover Disk, Modified Atwood Machine and Force Table)
  • Unbalanced Force Model (Wiggling Force Detector, Modified Atwood Machine and Atwood Machine)
  • Energy Transfer Model (Kelly’s Intro to Energy and Energy Transfer Lab)
  • All pretty standard, but that’s because it’s all great stuff and it works to introduce new folks to how their classrooms will change.

    One of the great things about modeling workshops is the distinction between student mode and teacher mode. For much of their time here, we ask the participants to work in student mode, acting as if they were students in a physics class, making mistakes and asking questions that they think their own kids will in the fall. We, the facilitators, use this to show how to navigate the issues raised by students (including pushback). By going through this themselves, the participants see how to transform their students from passive sponges to active participants in their own learning. We give plenty of time for teacher mode though, in which the participants reflect on the experience and how it will need to be modified for their own classroom setting. The three weeks we spend together here can be intense, but I’m hoping that each of the teachers, who have chosen to give up part of their summer for this experience, finds it rewarding and transformative.

    Screencasting (Proof of Concept)

    Inspired by the awesome ways in which Andy Rundquist has been using screencasts with his students (here, here and here), I decided to try to adopt this technique with my small class of six AP Physics students this year. I’ve always likened grading to a strange form of archeology, one in which the teacher works to unearth understanding from the artifact of student learning that is a written assessment. Too many times, students have come to me with a marked up paper and said “But I really meant….” or I see a final numerical answer that is correct and it is built on incorrect physics concepts. Instead of relying on only the written work, screencasts require the student to present their written work and narrate their solution. You might think of it as an asynchronous oral exam.

    I’d decided to pilot this now as our school is transitioning to a 1-to-1 laptop program. In another two years, all of my students will have this technology available daily and I want to find meaningful ways to utilize it. For the first test run, I assigned a lab problem involving the Flying Pig (available from Science Kit & Boreal Labs).

    Image

    In class, I set up the flying pig, timed it as it made 10 revolutions and then put the stopwatch in my pocket. Given a meterstick, the students made measurements of the pig and it’s motion. For their first screencast, the students had to determine what the reading on the stopwatch was. The students signed up for Jing accounts and executed the assignment without any real trouble. They reported that the act of talking to themselves was awkward and that their nervousness caused them to spend time practicing the presentation, so that overall the assignment likely added about 10-15 minutes of extra work.

    We had our second run at these two weeks ago. After introducing the dynamics of simple harmonic motion, I assigned a pretty standard AP problem (Knight, Chapter 14, #49) that involves a box attached to a horizontal spring on a frictionless surface. A second box rests on top and the students need to find the coefficient of static friction between the boxes that is required to keep the top block from slipping off as the system oscillates. This time, I specifically asked the girls to send me only the link to their screencast via email. The results were again great. This time, they were less nervous and had navigated the setup of Jing, so the screencast took less time and the narration sounded more confident. In both cases, I was able to pick up on some misconceptions including ones that might not have come across only in written work.

    For the second run, I also made screencasts providing feedback for the work they did on their screencasts. As I listened to the student’s narration, I scribbled down notes, sometimes including timestamps, and then simply checked these off as I recorded feedback. The process of “grading” these screencasts was quick and easy, but I ran into some snags with the workflow involved in sharing the feedback-casts with the students. As it stands now, my workflow looks like this:

    • Receive link to screencast from student by email.
    • Watch their screencast, making notes as I listen.
    • Open Jing, record feedback with their original screencast open in the background.
    • Upload the feedback-cast to my account.
    • Get the link for that cast.
    • Reply to the original email with the link to feedback.

    The process felt cumbersome as I worked through the class, so I’m looking for ways to make it more efficient. The shuffling of emails back and forth will have to go, as that is not scalable if I want to expand this next year to include more of my classes. Downloading the .swf files to my computer only to upload them to a Dropbox or Haiku (our LMS) leads to folders of files that I’d like to avoid. However, I may decide on a folder for each student that is on a shared drive or available via Google Drive. As the year progresses, the student and I could build a “set” of screencasts for each assignment – her original and my feedback which she could refer to throughout the year or even use in a digital portfolio.

    The other thing I’m trying to figure out is how to implement these in class. Right now, I’m thinking about a screencast per week involving a challenging homework problem, perhaps randomly selected from that week’s homework. The problem would correspond to a learning objective and be scored. Of course, this starts to bring up the possibility of students working together outside of class, so I still need to sort that out. I’ll see if I can post an example of student work and my feedback soon.