Stellar Stories

Last night, my 6-year-old niece and I were outside in the country on a clear night, looking at the stars, telling stories. Here is what she had to say:

“Stars are bright because they visit the sun during the day, and burn bright throughout the night.”

“Stars like to be in certain places more than others. In some places you can only see three of four stars, but in other you can you see a hundreds, or a million and three.”

“Stars hide whenever you turn on a light. But when you turn off the light, the stars come back out to dance, like at a party. Let’s pretend we are stars. First, we’ll turn off the light and hide behind the car. And then we’ll, turn it on and dance in the street.”

“When you look at the stars from the edge of the yard, they are over there, but then when we move to the house, the stars move. This happens because stars move in circles. See.”

“That bright star is from aliens–aliens that like to hop. They don’t hop too high, just little hops. Aliens grow and play. ”

“The moon isn’t out here, because it’s probably at my house.”

“Why are they called stars? They don’t look like the stars. Like the ones I draw. They just look like points. This is how you make a star. Those stars look nothing like stars.”

“I heard cows jump over the moon, but I don’t believe it… I don’t believe it, because cows are lazy.”

How we created a context

A course that emphasizes physics as a set of formulas to master has so many negative consequences. In this course, even I find myself at times needing to say something like, “Well, the formula for the force due to a spring is just different than the formula for the potential energy stored in a spring. One of them is F = -kx, and the other is PE = 1/2 k x²” It pains me to even think about speaking this… Well, actually, I take that back, it’s not so much the sentence itself; it’s the existence of a context in which such a sentence might actually make sense that is the real issue I have. So the question becomes, how did we create this context in our course?

I try to show you below how it’s not been terribly subtle.

Example #1:  Part of the directions given to students for solving 1D-kinematics problems on whiteboards

Example #2: Part of the directions given to students for solving projectile motion problems on whiteboards

Example #3: Part of the directions given to students for conservation of energy problems

Example #4: An excerpt from their readings on 1D kinematics

Example #5: An excerpt from their reading on conservation of energy

Example #6: Excerpt from their reading on angular kinematics

Example #7: Some computer exercises for them to work on for angular kinematics



Love this question

A very thin hoop is placed at the top of a ramp. Will the hoop (start to) roll without slipping?

Without doing the experiment, what would you want to be able to measure to help you decide? Why would these measurements help? How would you go about measuring them?. Once you’ve measured these things, how will you use those measurements to help you decide.

Seven Things I am Realizing

Only 7 of the million things I am realizing this year:

#1: Organization. I need to become better organized. In past, when most of my job was mostly being a researcher or student with teaching just on the side, I could be pretty dis-organized about teaching and it had few consequences. Once teaching became most of my job, organization has become key, but I’m way behind the curve on this one.

#2: Teaching Colleagues: Teaching an inquiry course like the one I am trying to do with the future elementary school teachers requires a lot of time and mental effort, and it really benefits from having teaching collaborators.  In the past when I’ve taught this kind of course, I was either co-teaching it or had plenty of people around who had taught a similar course. This year, this course I have is a lot harder to teach by myself, without colleagues to talk about the student ideas’ I am hearing. I am finding myself much worse off because I can’t engage in nearly daily discussions about where we might go and what we could do next.

#3 Evaluator/Teacher: There is a bit of me that really likes the fact that I don’t write the exams for my physics course, and there a bit of me that hates it. I like it, because it clearly puts me in the role of teacher and not evaluator. It’s my job to help them learn.  It’s someone else job to write a test that tries to assess that learning. I don’t like it, because I don’t feel like the tests are a good measure of learning.

#4 For students, especially students from other countries and certain minorities, academic and social isolation can be a big problem. I don’t know what to do about it, but it is something I am more and more aware of being here.

#5: I was really, really lucky not to have to work and go to school at the same time during college years. This was in part due to scholarships and in part due to my parents. So many students I know here work full time. Sure, I wrestled full-time in college. But wrestling was something I loved and I did it by choice. If I stopped wrestling, I wasn’t going to evicted or starve. Oh wait, I did starve myself often due to wrestling.

#6: It is a struggle to find time and mental space for research. This is both because I am teaching more, and teaching new classes. But it is also a struggle with fewer colleagues around. I am very very thankful for colleagues who keep tabs on me: Those who ask me to be part of writing or reading groups. Those who offer to help getting a paper out the door. Those who ask if I want to work on writing a grant together. Those who invite me to give talks. Without those people, it would be easy to disappear.

#7: In teaching, a lot of things matter in the day-to-day management of a classroom. Sometimes it’s the big things. Sometimes it’s the little things. I’ve learned that even if you have a handle on at a lot of the important stuff, it is still easy for things to go bad and go bad quickly because one small thing. Having established some rapport with your students (as individuals and a class), especially, about who you are as a teacher and how you care about your students as learners, can go a long way toward not letting a slip become a fall.

Student Projects: Ideas vs Concepts

Here is an introduction from a student project in my physics course, who investigated issues of symmetry in projectile motion:

“Why choose this subject to investigate? Out of all the options to research, why this one? The main and best reason I can give to explain why I chose this is just out necessity… In class, …through visualization [of motion diagrams]we began to realize a possible connection between the upward and downward segments of the path. We started to see the motion as reversing itself after the object reached the top of its path. It was from this, that we as a class began to form that idea that if you throw something up at a specific speed, then when it comes back down and gets to the same height that it must be moving at the same speed.”

And here is another introduction from a different student studying the same phenomena

“The purpose of our experiment was to determine if the speed of a ball being thrown up is equal to the final speed of same ball going down. The motivation for this experiment was in part based on Galileo’s own experiments with gravity. Galileo, an Italian physicist, determined that the force of gravity is constant and objects fall at a constant acceleration toward the earth. He determined this by dropping two cannonballs of different size off of the Tower of Pisa. The law of parabolic fall states, “The distance traveled by a falling body is proportional to the square of the time it takes to fall.”

There are likely many different things to see and ways of responding to these different introductions. But, these two different introductions tell the story about the difference between ideas and concepts. Kevin Pugh, an educational psychologist, writes here about ideas: “Ideas are possibilities that must be acted upon and tried out… Ideas are ways of being in the world… They are inseparable from human experience.” Writing about concepts, he states, “Concepts are established meanings (classics)…When intellectual products attain classic status, they become isolated from the conditions in which they had an original significance and from their potential consequences for everyday experience. As a result, their importance is reflexively accepted, but not fully appreciated…”

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