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# Encouraging women in STEM: What is a teacher to do? (I got published!)

This spring will mark 10 years since I stepped foot in the classroom as a student teacher. It’s always difficult for me to wrap my head around that length of time. By the 10-year mark, it would seem reasonable that a teacher could feel established and start making her way toward mastery…and yet, I still feel like a first year teacher. Due simply to life changes I have worked in five different buildings spanning 3 districts, on 2 sides of the state and have never once had the same set of preps. Only in the last two years have I felt I had the opportunity to truly build and grow a program and the students along with it.

The past two years have also been what can only be described as a special and unique experience. I had a phenominal group of students genuinely interested in the subject matter. So much so I managed to convince three of them that majoring in physics would be a great idea. All three are female.

My breadth of experiences has made me take a very critical look at what encourages student choices and what discourages them. I think too often we attribute outcomes to interest and drive, rather than inspiration and grit. I also firmly believe that while interest and drive are outside of my control, inspiration and grit are within it.

When I ran across a book review discussing a woman’s in a man’s world, specifically a “boy’s club” it immediately inspired me to write and share my experiences to expound on the question, “what do teachers do?” The answer to that question is far more multifaceted than one concluding sentence can contain.

My thoughts were accepted for publication in The Physics Teacher for the February edition, and I’m so thrilled!

http://aapt.scitation.org/doi/10.1119/1.5021425

# A Spin on Energy

Last week I ran a pretty straightforward lab:

1. Put 120cm of hot wheel track into a design of your choosing
2. Run a ball down the track
3. Record velocity with a photogate
4. Repeat at 10-12 locations
5. Plot the energy curves.
6. Plot Translational vs Rotational Kinetic energies and find the rotational inertia constant.

Students should see a transfer of kinetic and potential energy which makes sense. Of course, students should also expect to see a decreasing total energy curve because of friction constantly taking energy from the system.

I had two fun surprises I got to incorporate:

1. The shape of the TME curve

Inevitably this curve had a particularly sharp drop off at one moment in time. I had students sketch their tracks on their whiteboards in addition to their lab results. Do you notice anything? The largest drop off in TME corresponds to the moment where the ball is at the bottom of the hill. This serves as a great review of work and circular motion. Frictional force, as we know, is dependant on normal force. The normal force of the track changes and corresponds with its shape. We can actually predict the drop-offs in TME based on shape and even determine the work done by friction.

1. A group with “bad” data.

Their data wasn’t actually bad, they obviously had forgotten something when they set up their formulas in the spreadsheet. But was there a way to find this without redoing the whole data spread? Absolutely. After creating a large circle to share whiteboards, we honed in on the group where the TME curve was mirroring the potential energy curve. The rest of the data seemed good…there was an obvious trade-off of PE and KE…although the curves weren’t as high as they should have been. So what was the problem? I selected a student to draw in where the energy curve should be, based on the shape of their track and everyone else’s data. She drew in the curve. Next, I asked students to note where this curve was and where the PE curve began. It was at 0.3 J with PE starting at 0.6 J Then I asked them to note where the KE curves were at… they were at 0.03 J. Notice anything??? They were off by a factor a 10! Where could a factor of 10 be? Did they forget a 9.8? Did they convert grams to kilograms properly? cm to m? Upon examination of their equations, they found the missing 10 and…TA-DA! Fantastic results.

I think it’s really important to note the value of both exercises. The lab itself was relatively simplistic, but it lent itself to fairly complex conversations.  I think this is especially true for the group with the “bad” results. How often do our students present with this and either (1) Default to “well my data must be bad” or (2) Start from scratch, rather than locating the mistake? In this way, students were able to critically analyze, strategize and problem-solve. It turned out to be a really easy fix.

Oh and the slope of the translational vs rotational KE? Yea that came out to 2/5….exactly. That’s super exciting!

Teaching Methods

I visited my alma mater today. The entirety of Green Street on campus is closed to traffic due to all of the construction. Buildings have gone down and come up and I half expected time to still be frozen in the year 1967 in the physics building.

When I walked in I found quite the opposite. Not only newly renovated rooms, but there is actually a women’s bathroom on the fourth floor. (This was always a running joke)

The reason I spent 6 hours in my car today, however, was to visit the Physics 101 class. My former adviser, Mats Selen, has been working on a new project: the iOLab. The concept is simple, it’s a multisensor system in a box. And it can do everything your \$10,000 of Vernier equipment can do… for a little over \$100. It connects wirelessly to your computer and runs with free, opensource software that does all of the analysis our expensive programs run.

On the other side of the coin, however, is a radical change in how the introductory level classes are being taught. When students walked into the lab, they had done a pre-lab experiment earlier…..at home…..with their iOLabs. Quite simply, they made a stack of books, put another book on top by its edge and then looked to see how the force changed with the iOLab as it was placed at different distances from the book stack. Data were submitted ahead of time for credit. Students discussed the results at the beginning of the lab and then were given their task. It’s the classic peg-board demo, however, students had to find a way to relate the force to the placement of the probe if the pivot was located in the top corner.

This was the sum total of the direction given to students.

Within about 20 minutes all students were taking measurements. Some were looking only horizontally, others were looking both horizontally and vertically. Questions arose about the approach: if we change the angle at which we hold the probe the force will change. Are we supposed to do this with a horiztontal force too? I think that’s impossible.

They were told it’d be great if they came up with a mathematical relationship, but they’re just looking for the trends.

Within an hour students were plotting their data, recognizing it was an inverse relationship and running the curve.

One group really wanted to get the formula.

Another group recognized the torques should be equal and started calculating all of the torques. Percent uncertainty was one of the objectives focused on, so I wanted to see how well they were grasping that concept. I looked at the torques and noticed the values were .14, .14, .14, .15, .16. So I asked them how they were going to decide that those were constant and not increasing. They responded that they would have to determine their percent uncertainty and compare what was acceptable to those values.

Now, clearly there are major differences between high school junior and seniors and pre-med juniors and seniors, but at the same time, it was still remarkable how they were approaching the lab, developing their experiment and writing up their labs. It is something that very much excites me about the potential use in the high school classroom (and online classrooms, and college classrooms etc)

I also asked students about their previous physics experiences. About half reported they had taken physics in high school, ranging from regular level to AP Physics 1. ALL students reported that they felt they had a FAR BETTER grasp of physics now in this course, compared to their high school course. Several students who said this felt the need to insist they still had a great high school teacher 🙂

The message, however, is clear: we need to give our students the opportunity to design and evaluate their experiments.

Also, the iOLab is a very exciting new piece of equipment. Morten Lundsgaard, currently the Coordinator of Physics Teacher Development
Instructor, is hoping to run workshops and/or a camp for high school teachers. If you are interested you should contact him!

# Slicing a Cylinder for Moment of Inertia Integration

Guys….we’re in the throws of rotation. And at least one of my poor students has calculus immediately preceding AP Physics C. I feel so bad for her. The day we started she had made up a calc quiz, came to day 1 of rotational inertia, then went to calculus. Oh did I feel her pain.

Arguably the most difficult part of deriving rotational inertia is the visualization of how to go about the integration. I mean, let’s be honest, once we find how to express dm the integration is always an easy one.

Part of the problem is getting students to understand what it means to say things like dm, dV, dA, etc. They understand the definition linguistically, but it’s really hard to think of it practically. Tell them that dr^2 is zero and their minds are blown and bothered.

Day 1 of cylinders did not go well. Arguably, in part, because we were short on time. But also because the what why how was overwhelming.

I remembered a demo someone had shown where they 3D printed their objects to roll down the incline. They had actually made nesting cylinders, which then served as a great way to discuss integration.

I’m trying to think of a way to visualize each of the d-steps of the cylinder integration for my students with materials I have on hand. As I’m digging through the closet I notice the slinky coil. It’s nearly perfect!!!

Ideally, I wish I had one with nice thick coils so we could take about the cylinder with R1 and R2, but this will suffice for the most challenging part.

So imagine you have a cylinder of length L, and inner radius R1 and outer radius R2 and would like to determine the moment of inertia about its center…

First, as always let’s define rho, but we have to find dm in terms of r. So how do we do that?

Well, let’s take some horizontal slices, where each slice is dm… now we can see that dm = rho*dV…but wait… what is dV?

Well, if we make those slices infinitely small…is there really a volume left?

Ah! so dV is really dA, and we are looking at it across the length of the slinky, so dm = dA*L!

Conveniently, I know that A=pi*r^2, so dA = 2*pi*r dr

And the rest is substitution!

Teaching Methods

# Pumpkin Projectiles

You can smash your Halloween pumpkins! Each year at our science center, Discovery Center Museum, they will launch your pumpkins (up to 8kg) with their 10 ft trebuchet which is loaded with 400 lbs. (Why they limit by kg, but load with lb, I have no idea)

As a last minute thought, I blasted a text to my students: determine the initial launch velocity of the pumpkins. Double the points if you confirm the presence or absence of air resistance. Present in claim, evidence reasoning form. Have it ready for Monday.

Naturally, I couldn’t let my kids have all the fun (or the answers) so we went together as well. The pumpkins go way too fast/far/high to collect enough data at 60 fps, so I filmed in slo-mo (here is the original video), tracked the pumpkins on Vernier’s Video Physics app…

Of course, I had to see the graphs right away…oh so pretty…

then loaded the spreadsheet into excel and adjusted the times for the slow-mo camera. Additionally, since I had been given the specs in feet, I had to convert the units to meters. (I used the length of the base of the trebuchet to set the scale).

Oh how beautiful thou art, quadratic functions! Yes, air resistance is a factor, slowing the acceleration to about 3 m/s/s. There’s also a horizontal acceleration of about 1 m/s/s as well. Launch speed worked out in the ballpark of 12 m/s.

My kids who went are still crunching their numbers…we’ll see what they can produce!

Family

# Pumpkin Launching

Today was launch day at Discovery Center Museum

The treb is 11 ft high with a 400 lb counterweight.

It was awesome.

More on what I made my students do later…

Also…

Ferrofluid is awesome

Food

# Shameless Cookbook Plug

In addition to being a physics teacher  momma, I am also a clergy wife.

One of the needs I noticed within our community was a desire to learn about how our tradition of fasting is supposed to look in the practical lifestyle of an Orthodox Christian.

The cannons call for a strictly vegan diet during the fasting seasons, which include 40 days before Easter, 40 days before Christmas, 2 weeks in August, every Wednesday and Friday, and a few other special days during the year.

So I wrote this cookbook:

All of the recipes are simple and vegan, with an introduction to Orthodox fasting spirituality. We start our Nativity fast in 10 days, so it’s ordering time!

Family

# Magic School Bus Reboot: My Take

Last night I introduced my son to Magic School Bus. The real version. The one I grew up with. The one I realized I still have all of S1E1 memorized. (It’s the one where they visit all *nine* planets) There were a lot of things I realized about the original looking back as an adult/teacher/parent. First of all: no one considered the consequences of having Arnold march toward the “camera” and the camera is at crotch level? Secondly: I appreciate the immense diversity included back in the late ’90s. All of the kids are smart, and the different background characters are actually played by voice actors within those respective backgrounds. Third: The show shared information. In a very jam-packed manner. And in a manner where the students would make an observation and either fit it with a model and come to a conclusion (intestinal ville are like sponges!) or pose a question that Ms. Frizzle or another student would answer.  It was based on a field trip and so each episode is like a museum exhibit on magic, but in a very “hands on” sense.

The remake, however, seems to be trying too hard at its mission of “integrating technology”. The Netflix Revival Series, “Magic School Bus Rides Again” is produced by Stuart Stone, who most of us know as the original “Ralphie” from the 1990’s series. First of all, I get the idea that this series wasn’t made for me. But they clearly intended to cater to us now parent-aged fans: Ms. Frizzle (the real one) is still there, with Lily Tomlin reprising her role. The original gang is just a few grades ahead. Our favorite lizard, Liz, is still a part of the classroom. The opening sequence is identical, but with Lin Manuel Miranda putting his own twist on the meter of the music.

And then there was the first episode: Miss Frizzle of the Future.

Now, I must preface this with something related to my work-life. Our Creative and Performing Arts Academy has their fall musical this weekend. The show is Little Shop of Horrors. Audrey II has literally taken over the school.

Now, being the sheltered individual I was/still am and since Little Shop of Horrors was just slightly before my time, I was unaware of anything about the musical or film until this weekend.

So I’m sitting down to check out the new Magic School bus and what happens?

The New Ms. Frizzle brings in her very special magical plant.

And the plant is Audrey II.

Yea Arnold, I’m right with you on that one

So the kids go on their field trip to the Galapagos Islands. DA has an ipad in place of her books and the kids wear special goggles that trace out food hierarchies. It’s like tech integration for the sake of tech integration…which is definitely not best practice. Like, “hey kids, let’s wear these \$100 goggles which will let you see ONE thing! Ok, we don’t need them ever again!” yea, no thanks.

Meanwhile, Arnold, in an attempt to foil the new Frizzle, dumps Audrey II on the Galapagos.

Well… we all know how that is going to go…

Yea…

So the theme of the episode was invasive species. Arnold goes into the future and learns that the plant has taken over the whole island. They tried to tame it with bunnies, but the bunnies took over too.

Meanwhile, I keep waiting for the plant to speak…

So Arnold goes back to the past to stop the plant from taking over…but it still breaks through the pot. The new girl, we shall call her Audrey, drop kids Audrey II.

Fortunately, she is NOT mortally wounded and does not feed herself to the plant, neither does Arnold run into it with a machete, rather the whole class kicks in to wrangle it

Ms. Frizzle saves the day, and at the end of the episode I’m like

what

just

happened.

I wasn’t able to make it to my school’s production of Little Shop of Horrors, but apparently, it didn’t matter. I got the Magic School Bus Invasive Species Episode instead.

Needless to say, I wasn’t really impressed. I think the show tried too hard making us empathize with Arnold that, “hey kid, things are changing, and this show is going to be different” The majority of the complaints about the revival are related to the “cheap” animation and the apparent lack of creativity/weirdness of the new Ms. Frizzle, but I’m going to argue that if we can look past the superficial stuff, this revival has deeper, fundamental problems.

I recognize that generations change and we, as teachers, learn to adapt to that change, but I have a really difficult time lowering standards because “times are a-changing”. What do I mean by that? That somehow nothing is interesting if it’s not sensational. If the characters aren’t yelling at each other or at a situation that the show is boring. That this show needed to trade close, careful observation by its characters (hey, what’s that?) for sensationalism (oh my god, the plant is everywhere…and so are the bunnies). If the original show demonstrated to kids how to be scientists, the revival is demonstrating that cool gadgets are the only way to really see the world.

Maybe the other episodes are better, but my guess is given the rapid production of these Netflix reboots, there’s not much change to be anticipated.

Update 11/6: I stand corrected. Perhaps it was just the irony of the weekend. I watched the magnetism episode tonight and it was excellent. Like.. so much so I’m considering using it in my regular physics class in the spring. Explaining magnetic domains is so hard because it’s not tangible at all. I was really impressed. Granted, I still feel like the volume of science content just isn’t quite at the same level, but I certainly appriciate tacking such difficult concepts!

In My Class Today

# Flying a Plane with a Falling Bathtub

It’s 2014…I’m teaching 5 sections of Earth Science and visiting my parents. They have PBS on and we’re in the middle of this documentary about World War II. Except it’s not quite that, it’s actually about one of the escape attempts from Colditz Castle: the place where any POW was sent if they had attempted to escape the German prisons.

Now just imagine that for a moment.

It takes a special kind of person to plan, execute and attempt an escape. You need to be creative, clever and bold. ::cough::gifted kid::cough my students relate strongly.

And then the Germans think it’s a good idea to put all of these brilliant, audacious minds in one place.

So one of the prisoners gets this idea: let’s build a glider out of the stuff laying around the castle and launch it off the roof by attaching it to a bathtub. It’s a crazy idea, and it’s a perfect two-body physics problem, and I’m going crazy that I can’t show this movie to my students right now.

Now I teach a full load of physics and it is an annual treat in my introductory course. First, I have my students decide what types of things will need to be taken into consideration. The questions fly: where did they get a bathtub? Where did they get concrete? How did no one see them? They actually built the glider?

Then I have them do the two-body problem. I have had them calculate whether the original specs would have allowed the plane to fly, and also had them calculate the drag force from the test run on the model Professor Hunt riggs up when they need 1.1g.

The students get an incredible history lesson, and get to see the physics they just learned in legit action. I always pause the video when Professor Hunt is rambling off how he analyzed the data to determine the plane’s acceleration and ask my students if they caught it all. Then we go back to the video of the launch. LOOK! There are distances marked on the runway! We discuss how Professor Hunt would have determined the acceleration. How plotting d vs t is the best option. How we’ve been doing precisely that with the motion detectors in our recent pulley labs.

My first year doing this I split the film up over the course of three days. On the final day I asked my students to write reflective letters to Professor Hunt.

Professor Hunt actually obliged and wrote personal letters to each of the students!

I think it’s an amazing story and my students get a lot out of it each year. When I set the video up for 7th hour after AP Physics C one of my students said to another, “oh look what they’re watching today! I love that movie!”

Teaching Methods

# Modeling vs Intentional Modeling

“I use modeling, do you?”
“Uh…no, but I’m interested in learning about it”

I felt like such a noob when I had this conversation a few months ago because literally, everyone else at my group seemed to be doing this already. I was at a workshop on whiteboarding after a talk on standards-based grading and modeling and I thought, “wow, she really has it together… I have a LOT of work to do” (Does anyone else have this overwhelming feeling of inadequacy in the classroom all. the. time. or is it just the mom-guilt extended into the classroom?)

So I have started incorporating some things here and there as I’ve gone along, and I recently looked into Etkina’s resources (I started using parts of her book last year). As I poured over Etkina’s labs and our workshop speaker’s resources I realized: I HAVE BEEN DOING MODELING ALL ALONG! Mostly because it’s just the way I already think about problems. It just didn’t have a fancy name, and more importantly, I wasn’t always doing it intentionally as a teaching strategy.

I’ve decided that the intention is really the key in modeling as a teaching strategy. I think good physicists are good at models but bad at teaching them. We do it so seamlessly in our own work we fail to realize that type of thinking is not seamless or natural to the general public.

Cue modeling curriculum

Models are just any representation we use for a situation: pictures, free body diagrams, motion diagrams, graphs, mathematics etc. We need to work our kids like gymnasts, very intentionally using and practicing these models so that our students become flexible and natural at using them on their own for any scenario.

This is the paradigm shift: teach the model first, and the physics as a result of the model. Too often physics teachers (especially physics teachers not trained in physics) teach all this physics stuff, then all these equations for particular problems and then maybe shove in some graphs at the end. The problem is that students fail to see the bigger picture and physics becomes a class where students are attempting to memorize a million procedure for a million different problems, rather than learning a handful of approaches and selecting the best one or two for the problem at hand. The clearest example of this in my current classroom is how I am teaching two-body problems. I have made a huge deal about the fact that all of the physics is in the FBD. Because learning the general process for FBDs is a lot easier than trying to memorize separate processes for ramps, Atwood machines, modified atwood’s and oops! Now there’s friction!

The next most important part of this is to teach students how to communicate with one another using their models, and this is where the value of whiteboarding comes into play. I believe very strongly in letting the kids move around the room to see whiteboards without having a board representative at each board. The reason for this is that the students begin to realize that it’s hard to make sense of what someone has done if you don’t provide enough detail. Students can then ask these questions and leave them at the board before we come together as a whole group for discussion.

I decided to use modeling very intentionally in the classic coffee-filter air resistance lab. The original lab I had snagged from someone had a bunch of background info and then asked students to skets the velocity and acceleration graphs. I got really tired of marking the same things on everyone’s papers last year and realized this year that this is a perfect opportunity for modeling.

When students walked in today their desks were in groups of four with a whiteboard. I asked them for the following

1. A free body diagram at t=0, sometime before terminal velocity, and at terminal velocity
2. Acceleration expressions for each of the diagrams
3. position, velocity and acceleration vs time graphs.

It was so cool to watch them work, discuss and argue. The FBD’s were relatively easy, the discussions mostly about whether or not to put air resistance on the t=0 diagram.

The discussions about the graphs were far more interesting. Many students were working with the graphs as unique units, rather than considering the relationships from one to the next. Inevitably we had piecewise acceleration graphs and linear acceleration graphs and linear piece-wise vs curved velocity graphs.

I asked the kids to cite similarities and ask questions about differences. One group today started changing their board before attention was drawn to them. It offered a fantastic opportunity to review the graph models and review the relationships.

One of my favorites was a group that decided the curve of the velocity graph was quadratic, so they started taking the antiderivative for the position function. They noticed the constant slope portion in many of the other graphs and asked the question about it. Then they realized (#overachievers) the velocity graph wasn’t really quadratic.

I realize this particular example isn’t quite model-based learning through and through as I did not allow them to experimentally discover the exponential function relationships, rather after discussing that all of these changes were continuous I gave them a brief taste of the calculus/diff eqs ending in “solution is always in the form….” and hey, doesn’t that look like the curve we agreed upon?

We only collected data today, so I’m really curious and excited for what their write-ups are going to look like Wednesday!

I’ll keep you posted 🙂