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Learning about the Moon this Semester (Rambling notes for me, but you can read them if you want)

April 6, 2014

Late Jan, February, and Early March: 

~2 months of observations, light discussion, and moon journaling during inquiry units on other topics. The 1st month was done without much structure, except bi-weekly self and peer evaluations assessing mostly whether it’s getting done. 2nd month had more explicit focus on measuring angle moon and sun (after instruction on some methods of doing this), and still bi-weekly peer evaluations but evaluating more explicit expectations about what should be in an entry. During both months, we made in-class observations whenever weather and phase were amenable. We also discussed our moon observations and thoughts on the moon about 15-20 minutes per week, sometimes spilling over more. There was one day where I think we spent 1.5 hours talking about the moon. Early discussions often revolved around, ‘When did we last see the moon? When do we think you will see it again?”, “How come we couldn’t see the moon last night?”, “Why (in the world) could we see the moon out during the day?” “Where do we think we’ll see the moon and sun if we come out at the same time tomorrow?” “When was the last time in our journals where the moon looked like this?”, “Does everybody see the same moon the same way around the globe?”, “Why does the moon sometimes appear orange?”

When I do this again, I will more deliberately introduce and give practice with compasses and coordinating that with looking at maps of our school and their homes.

Week One of Focused Moon Inquiry

Day One: Initial Moon Ideas with Crumpled Paper Toss

Everyone was asked to spend 5-10 minutes writing about why they thought the moon went through its phases. Everyone had to use words and diagrams. Everyone knew they were going to crumple up their writing and toss it in the middle of the room, and then go get one that was no their own.

With elbow partners, students read and discussed the ideas and diagrams in the paper they found, and had to prepare a whiteboard to share what they had found about other’s ideas. Here is a smattering of the ideas

  • The phases of the moon depend upon a little bit of everything: weather, temperature, the seasons, etc.
  • The phases of the moon are the result of the earth’s shadow passing over the moon as the moon goes around the earth
  • The phases of the moon are caused by the moon spinning (around its own axis), 
  • The phases of the moon are the result of a “blow out effect”, whereby when the moon is close to the sun, the light from the sun overwhelms our view of parts of the moon (like how too strong a flash can “obscure” details in a photograph).
  • The phases of the moon are related to the various orbits and rotations of moon, earth, and sun, 

This served the purpose of getting ideas on the table, focused us on the role of trying to understand other people’s ideas, and introduced us to the real challenges of writing about your ideas so that others can understand. This whole unit builds toward writing a moon paper, using structures from “They Say, I Say…” by Graff & Berkenstein, so students have also had reading assignments from the book. 

Day Two: Creating a Community Moon Calendar

We spent most of the day, taking data from our individual journals and putting them onto large calendars I had created on the whiteboards around the room. I’ve tried in the past of “structuring this” in various ways, but I found it went well this time to let students just go up and put something on the board free-for-all style. Not one at a time, just mob style. The only structure I gave was, before hand, suggesting that we all share convention of whether shading in a diagram will show “what’s lit” or “what’s not lit” of the moon. Otherwise it gets confusing. I also encouraged students to check if someone else in class had a similar observation before putting anything up and encourage students who hadn’t gotten up to do so. I also let them chat off-task if they wanted.

It was a low pressure situation with a relaxed tempo and vibe. Many groups were up and adding things to the calendar, discussing. Other were comparing notes from their journals at their desks. Some were hanging back. A previous me would have thought ill of the laxadasical flow and pace, which included a real lack of structure and even permitted off-task talk. Someone watching my class could have easily just been confused as to why I was just letting students wander around, some on task, some off task. It could seem to someone else that it took us a lot of time to do this, and someone could have been wondering if this could be done more efficiently. I think the feel and pace was near perfect. [Side Note: In general, my feeling, thoughts, and even response concerning off-task talk has changed dramatically over the last 3 years.]

Afterwards, we started looking for patterns. Patterns we discussed were ideas related to waxing and waning about how it seems to take 28-29 days to repeat. Other patterns focused on what side of the moon was lit and what time of the day. Next time I want to scaffold this a little bit towards “proposing possibilities” language such as “I’m noticing that, I’m wondering if…” One reason is that some patterns students will suggest will be “correct” (from scientist’s perspective) and others will not. I don’t want to be put in the position (now) of having to be the arbiter of that. Second, I want students to feel OK in proposing possibilities. Third, I want every student to be in the position of deciding whether or not they understand the pattern being proposed, whether or not they agree that pattern might be there. 

Day Three:  Analyzing Writing Moves (and Modeling a Specific Moon Day)

Students had just submitted their first writing assignment the previous night. I took an example from one student who had decided to write about the blowout theory–what the idea was and why they had come to believe that the blowout theory could not be an explanation for the moon phases. The assignment had to been to write about one idea from class and then respond to it–either agree and give reasons or disagree and give reasons.

In class, students were given the excerpt and the prompted to:

  • (A) Highlight phrases within the text that signal to the reader whether they author is discussing what “Others Say” about the moon or what “They say” about the moon. 
  • (B) Highlight phrases within the text that signal to the reader that an idea is about to be clarified, elaborated, or compare/contrasted. 
  • (C) Highlight any other important phrases or words within the text that you think standout. Be ready to explain why you chose a phrase, and what purpose you think that phrase serves in helping the reader understand the text.

Here is the (snippet of) student writing that was analyzed and discussed:

“One observer believes that the Moon’s phases are in direct correlation to the specific distance of the Moon from the Sun as it travels in an orbital path around the Earth. They say that when the Moon reaches its closest possible orbital position next to the Sun, the bright sunlight overpowers the lesser light of the Moon, thereby making the Moon virtually invisible to our eyes. Then, as the Moon continues to travel in its orbital path around the Earth – it is simultaneously changing in its distance from the Sun – and, that is what causes us to observe incremental changes in the phases of the Moon. This theory seems to imply that the further away the Moon moves from the Sun, we are then able to see a larger area of the Moon’s surface. 


Personally, I disagree with the first observer if by their explanation they are implying that the Moon is a lesser source of light than the Sun. Based upon that premise, we wouldn’t be able to observe different phases of the Moon’s surface. Instead – depending upon how far the Moon is away from the Sun along its orbital path around Earth – we would only see varying intensities in brightness of the light upon the entire surface of the Moon itself. Thus, I say the Moon merely reflects the light which originates from the Sun.”


After students worked in groups to read and discuss, we put the text under the document camera, and students suggested lines to highlight and gave reasons. 

After the writing discussion, we decided to pick a day/time that we had all made the same moon observation and try to explain/model what was going. We chose a day from our moon calendar where we had made an in-class observation–that way we knew everyone had seen the same thing and had a moon journal entry. The observation we picked was a crescent moon seen to the right of the sun around noon time. Every group had available to them for modeling– a globe, a styrofoam ball, a light bulb; whiteboard with markers; they also had a envelope filled with various two-dimensional laminated cutouts of suns, moons, day-time skies, night-time skies, grass, people, and even words like, “Noon”, “East”, “Up”, “Sunrise”, “Midnight”, “North”, etc. Students worked in groups trying to create a model that would help show them what was happening that day to create a crescent moon seen to the right of the sun. I circulated around as students engaged in the task, but we didn’t have time that day to share out anything. Students didn’t necessarily stick to the task of the crescent (which was fine). Many students were engaged in modeling the moon’s phases more broadly. Here are things I noted that day:

– One group had decided that the moon could not orbit around the equator, because it would seem that there would never be a full moon. They were excitedly toying with the possibility that the moon went over the pole’s instead.

– One group was becoming increasingly confident with the shadow theory.

– One group was becoming increasingly disenchanted with the shadow theory

It’s not true that the groups were so homogenous, perhaps it’s better to say that these three things were happening. There was a loose correlation with groups. But I know there was one anti-shadow person in the group that was swaying toward the shadow theory. And I know that two students in particular were driving the disenchantment with the shadow theory. 

I’ll write later about what happened the following week. I actually had to miss class the following Monday and so students had to run class without me. 

Here’s quick outline for me to remember:

Monday: Student-led Class–explaining the shadow theory in depth; and introducing objection’s. [Bubble Popper vs Brick Builders]

Wednesday: Building Foothold Ideas: “What We agree on, What we don’t agree on, What questions we still have”; Shadow Theory Revisited

Friday: Olaf’s Cousin who lives in a Rocket Ship; and Spinny Chair Modelling

Physics Pub Questions

March 30, 2014

One of the students in our physics teaching program has been organizing, “Physics at the Pub” events. Basically, a bunch of us get together to talk physics over beer and food. So far, we’ve met twice, and we’ve had some really fun, interesting conversations.

The first time, we talked about this question. “Why when you pour beer in the pint glass does it seem like the beer extends all the way to the very edge?” Like we know (and can see when the beer isn’t there) that the glass boundary has a definite thickness to it. So the beer must really be “inside” of the glass rim, but it looks like it extends all the way into the glass.

Last night, we started off by talking about the Veritasium’s bullet in the block question, but spent almost all the time talking about this situation: Why does a soccer ball go farther than a bowling ball when you kick it? Most people’s initial response is that “same kick” = “same force”, and thus by Newton’s 2nd law “Same force over more mass means less acceleration”, and then finally “less acceleration means less distance”

But, pretty quickly the discussion comes to be about what “same kick” means. It turns out, there are lots of reasons to be suspicious of the assumption that the “same kick” results in the same force, but it’s challenging work to reconcile that with the commonsense idea that you “kick with a force”.

What I love about this second question (which I’m pretty sure I was introduced to by David Hammer), is that, for students, resolving it involves having to really contend with many, many concepts all at once: what force is and isn’t, the limitations/challenges of Newton’s 2nd Law reasoning in the context of non-constant forces; their level of commitment to Newton’s 3rd Law, carving out how we should think about the magnitude of acceleration in concert with the duration of acceleration, impulse and momentum ideas, inertia and what we mean by that, and struggling with how t think about the “stiffness” of materials (and modeling that with springs). Energy typically gets in the mix as well. 

The second thing I love about the question is this: Everyone knows the answer. The soccer ball goes farther. We just can’t agree on how to adequately explain it.

The third thing I love about the question is this: It reminds me that, if you want to find out what students think and/or engage them in deep physics, you don’t need an elaborate/ contrived scenario. In fact, the more everyday and seemingly simple the situation is, the more likely you are to engage their thinking. That said, this question should be probably saved for students who have a good deal of facility reasoning about Newton’s laws and who are likely to recognize the need to persist in trying to reconcile inconsistencies.


Rambling– or Interesting Things I would blog more about if I had time

March 30, 2014

I.  A clear majority of students in my physical science course for future elementary school teachers do not actually plan to go into teaching. When I ask why, they say that it’s because teachers they have come to know and/or meet all tell them they should “run away” as fast as they can from public school teaching. 

II. Because I am teaching 2nd semester physics, I have many more students with whom I interact for an entire year. I enjoy having these year-long relationships with students, because I get to know students much better. There are also real big advantages with the amount of trust that students have with me. We can do things and persist in things that are confusing, because they have been there enough times with me to know that it will pay off, AND that even if one time it doesn’t pay off, it’s OK, next time it will.

III. In my step II class (the 2nd course in the UTeach sequence), a hot topic of discussion from students has been their own challenges and successes in “getting students to say what you want.” This phrase comes up so often in class (from students, not the instructors). It’s a real window into how they are conceptualizing inquiry teaching so far. While I understand that they are grappling with the very real difficulties of asking good questions and facilitating discussion, their language here suggests that the students and I have different views about the purpose of questioning and discussion. I don’t think they yet see that questioning and discussion serves a role in helping the teacher (and students) find out what everyone is thinking. 

IV. Several of the physics teachers in our area have really taken up some of the discourse moves we have talked about and practiced in our monthly workshops. One teacher in particular says that “re-voicing” and asking students to “re-voice” has transformed her classroom practice. While many teachers really enjoy our workshops, some really “take up” practices more readily than others, and I’m curious about when and why this does and doesn’t happen.

V. I have an amazing group of students in my physical science class. We do lots of serious intellectual science almost everyday, and do it while having a lot of fun. It is so much fun to be in that class, laughing all the time. Yesterday, I had to kick students out of class (30 minutes after it was officially over), so I could start my other class in the same room. I wish I could tell you more.

VI. Being in my third year working with the future physics teachers has its advantages. Before, almost every student I knew was “new” to me, and getting students to “come around” was hard work. Now, I’m almost never teaching a class, where there isn’t a mix of students that are new to me, some I know a bit, and some I know really well. This has huge advantages, because the newer one’s learn how to “participate” implicitly by observing how the more experienced one’s participate. Students more quickly and readily pick upon the fact that “you have to talk”, “share and listen to ideas”, “defend your ideas with reasoning /evidence”, and importantly realize that we all understand the physics less than we thought (and that it’s OK to be wrong and admit you don’t understand something). 

VII. I am almost always barely getting by in doing what I have to do. It is stressful, but for the moment, things are going really well, so it makes it feel so worth it. While I’m quite content right now, I have to admit to myself that I don’t know how to get an appropriate work-life balance. I know that my current balance can’t go on forever, and I’m struggling to see how to make it work. Ugh.

Everyday Ideas–Pee Theory

February 26, 2014

One of the powerful ideas we’ve had in inquiry class this semester is called “Amy’s Pee Theory”. It’s an idea we’ve returned to again and again in explaining phenomena. Amy’s pee theory states that if you pee a normal size amount in a very large pool, no one will notice. The pee (to be sure) is still there, but it’s been spread out over such a large thing, that it’s not concentrated enough to have a noticeable effect. Peeing in a smaller container of water, such as a toilet, results in a more obvious effect (yellow color), because the pee is concentrated in a small container. This idea is our class’s instantiation of beginning to think about a thermal reservoir.

Last week, our class discussed the energy tracking of a battery-powered fan. We spent most of our time trying to decide whether the room’s thermal energy increases, decreases, or stays the same. We touched upon lots of everyday experience–running the thermostat in your house switched to “A/C”, “Heat”, or just “Fan”; actual temperature vs. “feels” like due to wind chill, fanning to “cool yourself” off, you don’t seem to cool down the room; how the moment you stop fanning, the cool feel goes away; how ridiculous it seems that you could really cool off a room by having lots of people fanning, vents in your car, etc.

Eventually, people were convinced that fanning didn’t actually reduce the temperature, but we didn’t have an explanation for why you felt cooler. The idea that was eventually was proposed was, “Fanning helps the thermal energy you’ve produced around you go away, by blowing the warm air away from you.” Several said that there mind was blown at hearing that idea.

Eventually,everyone agreed a room should technically get hotter, but you wouldn’t be able to tell via “Amy’s pee theory.” The room is so big that the little bit of thermal energy put off by the motor wouldn’t make a big difference. This nicely motivated why we should try the experiment with a fan in a very small “room”. So we ran a fan inside a small cooler for 10 minutes while we went outside to make moon observations, and the temperature inside the cooler had risen by 12 degrees. Pretty cool. Upon opening the cooler, pretty soon the cooler was back to being normal temperature, because the “pee” that we had kept trapped in a toilet had now spread out into the pool. The room was not measurably hotter as a result.

After the experiment, someone blurted out remembering a long time when their house had been flooded.  To dry out the house, they had to bring in dozens of industrial fans, and they recalled how freakin’ hot it made the house. Bringing in dozens of huge fans was like getting several bus full of kids to pee in the pool. 

Sometimes, things go well…

February 15, 2014

My inquiry class is going quite well this semester. The skills that this class has picked up quickly and use regularly include

– Re-voicing and paraphrasing what others are saying

- Asking questions about others’ ideas to get more information

- Asking questions to make sure we understand each others’ ideas

- Summarizing, comparing, contrasting different ideas that have been said

- Telling someone if/when their ideas make sense (even if one don’t necessarily agree), and why it makes sense.

- Talking to each other for extended periods of time (without looking at me).

- Using tone of voice / eye contact to indicate interest, care, and humility (rather than dismissal, indifference, and righteousness)

- Posing honest questions and making honest statements

- Using tone and body language that communicates that everyone is free to change their mind

Part of this reminds me that “being” a good listener and “being” engaged consist of things you actually do. But I’m also reminded of just how easy it is for everyone to do these things when everyone feels the right way–feeling safe and having a sense of belonging. Of course I know that there’s feedback between feelings and behavior: the students feel the way they do because of they way we are all behaving, but we are also behaving these ways because of the way we feel. It’s mutually reinforcing. And, of course, when these feedback loops are going the right way, it seems easy, like how could it be any other way. But I know that other times, when the feedback loops are going the wrong way, it can seem impossible. Cherish the good times.

Brain Dump: Good Argumentation / Never Used Before Talk Move

February 15, 2014

One of the topics we teach in second semester physics is blackbody radiation. The typical kind of scenario students would be asked about is, given the temperature of a star and information about the size and orbit of a planet, determine how much energy arrives on the planet each second. One of the main difficulties students have is deciding how to use the relationship that intensity = power/ area. There are lots of different energies, areas, and intensities to consider, so students who are used to plug-n-chug can easily fall apart here. Since we introduced the topic two weeks ago, I’ve been starting each day with various discussion (clicker) questions asking student to think about intensity, energy, and power qualitatively. We’ve had lots of good days of discussion stemming from this and progress is certainly being made, but students’ handle on the ideas seem to be quite elusive and fleeting with lots of side-steps and backslides, even for the students who don’t usually struggle.  On Thursday, I asked the following question to start our day, which pulled us into a really good discussion that lasted 15-20 minutes or so:

Assume you know how much energy is emitted from a star each second, Es. You want to find the intensity of the light arriving at a planet. Which calculation should you use? The question included a diagram that showed three distancse: Rs, the radius of the star, Rp, the radius o the planet, and Rsp, the distance between planet and the sun. The four options where.

A. Es/ 4πRp²

B. Es/ πRp²

C. Es/ 4πRsp²

D. Es/ 4πRs²

Students thought to themselves, voted, and then talk in groups. When students re-voted, we were split between B and C, with a few unsure whether it was A or B. We’ve been getting used to these kinds of discussions, so I asked a few students to explain why those chose B.  The basic line of reasoning was that we were interested in the intensity at the planet, so the relevant area had to be the area of the planet, because the planet that was catching the energy with its cross-sectional area.

Instead of letting people voice an argument for C, I said that those who picked C had to explain what they was wrong with B without explaining why they thought C was correct. I motivated this by talking about why so many hot button issues arguments are unproductive, such as abortion rights, whereas everyone just keeps repeating their arguments without listening to the other side.

One really nice argument, which ended up being convincing to most in the class, was this:

- Es/ πRp² says in words that you are taking all the energy from the sun and spreading it over the area of the planet. This can’t be right because not all the energy from the sun gets to the planet. In fact, most of energy misses the planet because it goes off in other directions.

I made sure at least one other student could repeat the argument, and then another argument was made: This argument was about how we could actually “correct” the equation so it did give the intensity at the planet. The argument was that if the “area” you want to divide by is the area of the planet, than the numerator has to be energy arriving at the planet Ep, not Es. Intensity *is* an energy divided by an area, but to get the intensity of the planet using the area of the planet, you have consider the actual energy arriving at the planet, so it would be Ep/πRp².

By the time we got around to asking for arguments for C, most students were convinced it couldn’t be B, but formulating good arguments for C was hard, and it took a bunch of back and forth among the students before a really compelling argument to emerge. The discussion was really juicy and students were really listening, but I had a feeling that while the “class” a whole was getting it, many students still needed an opportunity to pull it together, consolidate. So I had students vote with thumbs up, thumbs side, and thumbs down, whether their understanding was , “I understand the reason why it must be C, and could explain it,” “I think I understand why it must be C, but I’m less confident I could explain it someone else,”, “I’m still not sure I understand why it must be C”. The room was split about half between thumbs up and thumbs to the side. I said if your thumb was to the side you had two options: you could look to a person with their thumbs up and tell them that you want to practice explaining it to them OR you could ask them to explain it to you one more time. I’ve never used that move before (giving the students who are unsure the option to either practice explaining or receive an explanation), but for whatever reason, it was the right move at the right time. The entire class in pairs and groups erupted into conversation and spent a long time explaining to each other–serious, passionate, intellectual talk with gesturing and smiles. I just stood at the front of the room and watched and waited for the talk to subside. It took a long time. I had a few more clicker questions, which we breezed through. Many groups told me that while they were discussing alone, they had actually spontaneously asked of themselves and discussed the questions I had posed.

I wanted to jot down this brain dump, because I thought the two counter-arguments were really fantastic, and I wanted to think about why this particular talk move worked so well. Part of it is that they were just primed and ready to talk about it more, but I think there was something about putting the power in the hands of the person who doesn’t understand. They were in control-they could demand to hear an explanation or demand that someone listen to them.

Things that are keeping me busy (and away from the blog)

February 8, 2014

Monthly physics teacher meetings:

Since September, our Department has been hosting a monthly event for local-area physics teachers. We usually have some time at the beginning for demo-sharing on a specific topic area, then we provide dinner and some time to chat, and we usually end the evening by engaging the teachers in some sort of physics/physics teaching activity. So far we’ve had 5 meetings, and we’ve had lots of good feedback from teachers. About 6-20 teachers have been attending. Hoping to continue to nurture this and thread this into some grant proposals.

Learning Assistant Program Pilot:

Last semester, two faculty in our department attended the LA workshop at UC Boulder. This semester we are piloting some curriculum changes and use of learning assistants. Right now, we are only implementing in two section of  our intro physics course and most of our LAs are already physics majors in our physics teaching concentration; but the plan is to implement more widely and to recruit students to be LAs for next academic year We’ve applied for some money that will hopefully help out with that. I’m not teaching in these section, but I have responsibilities for running the prep session with the instructor and the LAs for instruction each week. I have a undergraduate student who is also helping to collect data regarding this pilot implementation.

Two New Preps:

This semester, I’m teaching three courses, but two of those courses are ones I hadn’t taught before at MTSU. The first one is the second semester of the algebra-based physics course, which covers optics, modern physics, and electricity and magnetism. It’s been nice to have a different course to teach, but it’s meant more prep than usual.

I’m also teaching a new course for the first time. We had previously had a one semester seminar course called “Physics Licensure”, which was intended originally to be a self-study-kind of course for future physics teachers to make sure they were prepared for the Physics Praxis. We’ve made that a year long seminar now, in which we focus more on developing conceptual understanding / qualitative reasoning with 1st-year physics topics (and less on praxis prep per se). Students also have responsibilities for working on AP physics problems. This semester is the first time the second-semester of Physics Licensure is being offered. Right now the two courses are still kind of playing the role of “band-aid”, making up for deficiencies in our first-year courses. We are working to improve our intro courses (see above), so the nature of these courses may shift.

On top of this, I’m working on a grant that doesn’t overlap with any of the efforts described above and trying to finish a paper that’s been in the works for years that also doesn’t concern these efforts. The next time I write a grant, It’ll need to be more synergistic with my service and teaching efforts.


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