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 🙂

Classroom Issues

# Squishing Miss Giggles

We have a problem.

It’s a big one.

And it’s one of those problems we, as teachers, need to fix.

Unfortunately, some of the teachers are part of the problem.

Her name is Miss Giggles. She’s actually a virus. She preys on girls who either lack confidence in their skills or actively hide their skills in order to maintain social status. Miss Giggles boasts a high of popularity, boys, and conformity.

The reality is much darker.

Miss Giggles undermines that which is unique about a girl who is talented. It undermines the strength of a woman. And it forms a false perception of the girl she has infected, to her future detriment.

You would like to think that as this girl matures, goes to college and enters the workforce she will develop antibodies to Miss Giggles and move on. Unfortunately, that is not so.

I had attended a physics teacher association meeting and a colleague infected with Miss Giggles got up to present. She literally giggled during the whole presentation. I know this is her personality, and I also know she is an amazing teacher and brilliant, but quite frankly in front of our group of peers, in that moment, she came off as silly and stupid. In fact, they were unable to answer the question they had sought out to answer in the first place, so by ending the talk with a jovial, “and we have no idea” and a laugh, it seemed as if she had wasted the mega-grant she had obtained. All the while, her arguably inferior male partner came off as put together and knowledgeable.

At a meeting at the start of the school year, we were asked to watch a video an give our impressions. Nearly every female gifted teacher who responded started her response with “I’m sorry if this isn’t right, but I thought…” I was infuriated. WE WERE ASKED OUR OPINION! YOU CAN’T BE WRONG. And yet my female colleagues were dumming themselves down in front of our (female) principal and peers.

Psychology tells us three things: first impressions are quick to form, long-lasting, difficult to change, and often correct.

Miss Giggles creates a grave problem here: she creates a first impression that is incorrect, but very difficult to change. Meanwhile, we live in a world where women still strugle to have equal status with men and are minorities in highly technical fields such as physics. We have to prove our worth moreso than our male counterparts. Yet, there are a huge group of women who are undermining these efforts for equality!

I often have this conversation with my students: first about the science of impressions, and second that people will form those impressions based on how you carry yourself and how you speak. (Since they are formed in the first 10 seconds). Too often our girls will sell themselves short, “I don’t know anything! I’m going to fail this test” and more often than not, these are the smart ones. I quickly and semi-jokingly snap back at them and follow it up with a lesson in gender bias: first of all, everyone is going to believe you and judge you and secondly, would you ever hear a guy saying that? Does that mean he is actually smarter than you? Obviously, the answers are no and no. In specific cases I have had more serious, private conversations because when I know the student plans on majoring in engineering or physics I tell them that that is their goal this school year: to work on their presentation of themselves as confident and intelligent, because they are.

As teachers, I believe we have an incredibly important role with our students as mentors. First to model behaviors of strong, capable women, and secondly to tell them to cut the crap when they start exhibiting any symptoms of Miss Giggles.

I really think Hidden Figures was an incredibly powerful movie. Not just because of the story it told, but because of the brilliant job it did at portaying these women’s personalities and attitudes in a man’s world where they would certainly not be viewed as equal by their peers.

In her commencement address for Hampton College Katherine Johnson said, “Whatever I’m doing, I do the best that I can, not the best that’s available, but the best that I can, so I can’t give you any more, you have to get something more from someone else. But at all times, at all times, I do my best. You will do better if you cause other people to want to learn and you will do it better, too, all the time. You want to learn, want to teach, want to help.”

Her words are so wise and I think should be taken to heart by each of our students. Be your best. Be confident in your best.