MOM: Let’s see. It says here: you pick choice C too often; you spend more time working on even numbered problems than odd ones; you watched 3 videos all the way through, and rewound portions of 5 other videos. And last, it says your answer patterns most closely match those of women over age 25 who live in Canada and prefer One Direction over Justin Beiber.
BILLY: Does it say why I’m struggling with algebra?
Nothing earth-shattering here. I just wanted to share the activity we worked on today, which was an introduction to quantitative energy conservation by doing a video analysis of a bouncing ball. (Up until now, we were only doing qualitative energy pie charts.) Here are the handouts and the video:
Feel free to edit and reuse the handouts as you see fit. They’re not perfect, but I figure it’s better to share them than having them collect dust on my flash drive.
PS: I’ll sheepishly admit that I don’t do the whole suite of paradigm labs in the Modeling unit to mathematically derive the energy equations from experiments. But we do some simple qualitative demos/experiments to discover what variables would be in those energy equations. We start by talking about how the further a rubber band is stretched, the more energy it stores. Then we launch carts into a rubber band “bumper” (i.e., big rubber bands from Staples and two C-clamps) to qualitatively see the energy stored.
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In doing so, we see that the cart’s kinetic energy depends on its speed and its mass. (Or is it weight? What would happen if we repeated the experiment on the moon?)
For gravitational energy, we can repeat the experiment, but have carts rolling down an incline. Or use the rubber band to launch the cart up the incline. I’ve also dropped balls into sand and looked at the depth to which they get buried. Either way, we see that gravitational energy depends on height and weight. (Or is it simply mass? What would happen on the moon?)
For elastic energy, we already know it depends on the distance the rubber band is stretched. Then, we can swap out the rubber band in the bumper with a stiffer/looser one to see the effects of the spring constant on energy stored.
Then, after we predict what the energy equations might look like, I just give them the actual energy equations, or have them look them up. (Gasp! See Schwartz’s A Time for Telling, aka Preparation for Future Learning.)
So, modelers, what am I missing by not doing the full-blown energy paradigm labs? How do you introduce the quantitative energy equations?
Which is more difficult to teach/learn: Algebra or Fractions?
Last week, I was a guest at Discovery Education’s “Beyond the Textbook” forum. During one of the breakout sessions, my group (Christopher Danielson, Angelia Maiers, and Chris Harbeck) got to discussing about how hard it is to write math curriculum and that no digital textbook would be worth its weight in bytes if it didn’t acknowledge that. Christopher Danielson wrote a great blog post which both summarizes and expands upon that discussion.
To illustrate that most non-math teachers don’t quite get the nuances involved in science and math instruction, I asked Angela which concept she thought was more difficult: algebra or fractions. She answered algebra without hesitation. And I said I felt fractions were more difficult. I said that my 8-year old son has no problem with algebra: 5 + [_] = 7. What goes in the box?
But what does 3/4 mean? Is it 3 objects out of 4 objects? Is it one object split into 4 pieces, but we only care about 3 of those pieces? Is a ratio of 3 things to 4 different things? Or is it division and we are taking 3 objects and splitting them evenly to 4 groups? Is is 75%? Or is it 0.75?
Angela was blown away by this discussion and wondered how other people (math folks vs. non-math folks) would respond. We decided to conduct a little experiment. We would both ask our PLNs the same question and compare responses. My prediction was that since my PLN tends to have a math and science focus, the majority of my followers would say fractions are more difficult. And I predicted that Angela’s PLN, which is more broad than mine, would say algebra is more difficult.
Here are the results:
I was correct in my predictions, but I was surprised at how my PLN was much closer to a 50/50 split rather than a 2:1 split like Angela’s. Here’s the raw data — it’s interesting to comb through the responses to read why they chose algebra or fractions:
Recently in Dietrich, Idaho, a biology teacher is under investigation after several parents complained about a lesson on human reproduction. The parents said they simply wanted more notification about class content. I think such notification is a great idea, and thus my letter to you.
Right before spring vacation, I asked my physics classes what topic they wanted to learn about in the fourth quarter. The students overwhelming chose astronomy. They also made it clear they wanted to learn about how and why the universe works as it does, rather than simply memorizing the phases of the moon and names of the constellations.
As a result, we will be talking about some sensitive topics. You may wish to have your child opt-op of class on those days. These topics include:
Newton’s Theory of Universal Gravity. The driving force behind most astronomical phenomena is gravity. And, of course, it is “just a theory.” There are many problems with Newton’s Theory and it can’t explain everything we observe. I anticipate some of you may wish to pull your children out of class on those days so it doesn’t conflict with the Theory of Intelligent Falling they might be learning at home.
Moon Landings and Space Exploration. This is another controversial topic for some families. A decade-old Fox documentary questioned whether men have really landed on moon. It used physics in an attempt to beat NASA at its own game and show the moon landings were a hoax. I understand if you would like your child to stay home when we talk about the composition of the moon rocks the astronauts brought back and how NASA engineers applied Newton’s Theory of Gravity in order to make those journeys happen.
Despite these sensitive and controversial topics, I do hope you’ll still keep your child in class. It’s always best to know both sides of an issue in detail.
If you have any questions, please don’t hesistate to contact me.
I have the honor of being invited by Discovery Education to attend their second “Beyond the Textbook” forum to be held this Wednesday and Thursday at their headquarters in Silver Spring, Maryland. The event is spearheaded by Steve Dembo and, in exchange for travel expenses, he gets to pick my brain about digital textbooks, resources, and curriculum. There will be 18 other outstanding educators as well, including my edu-heroes Christopher Danielson, Michael Doyle, Karl Fisch, and Tom Woodward.
I keep thinking about what a physics iBook would look like. Not a book for consumption, as with a traditional text, but rather a book to enable exploration. So what would a student see when they first opened such a book?
Students should be learning to doscience, not simply learning aboutscience. They should be making observations, posing questions, conducting experiments, finding patterns, analyzing data, and sharing their conclusions.
In this sense, the iBook would function more like an electronic lab notebook. As with curricula like Modeling Instruction and ISLE, students would create the physics content from their own investigations and evidence, rather than deferring to authority.
Actually, the iBook wouldn’t be completely blank. While it would initially be empty of content, it would be chock-full of toolsto help students collect and analyze experimental data. Software like Tracker for video analysis, VPython and GlowScript for computation and visualization, LoggerPro for graphing and electronic data collection, along with PhET simulations and Direct Measurement Physics Videos for conducting virtual experiments.
In the realm of traditional physics textbooks, only a few make it a priority to incorporate experiments into their storylines. Three that come to mind are:
FIGURE P-2 Electronic temperature sensors reveal that if equal amounts of hot and cold water mix the final temperature is the average of the initial temperatures.
For example, here’s a video of a momentum experiment, followed by the corresponding section of the text.
But, as you can see, the text does the analysis for the student. In my opinion, this would make a good reference only after the student has completed a similar activity on their own. Fortunately, her text also comes with a workbook that asks students to do this sort of scientific reasoning on their own:
Also taking the “experiments first” approach is Live Photo Physics Interactive Video Vignettes, a collaborative project by well-known physics education researchers Robert Teese, Priscilla Laws, and David Jackson. During a vignette, students are asked to make predictions and do video analysis on-the-fly. Here’s a preview:
Science is never done in isolation, however, so the iBook would come equipped with tools for sharing data, content, photos, videos, and resources among students and between teacher-student.
For me, going beyond the textbook means giving students a toolbox rather than an instruction manual.
What’s your vision for the future of textbooks?
You can follow along with us at the Beyond the Textbook forum this week by searching for the Twitter hashtag #BeyondTextbooks.
You are a game designer for Rovio Entertainment, the company that makes Angry Birds. The human resources department wants your input. They are hiring several programmers to build the physics engine for Rovio’s newest game. Here are the demo videos from the top four applicants. Which applicant(s) would you recommend for hire?
These videos were not created by me. I found them online several years ago, but I can’t remember where. If anyone knows, please tell me so I can give the creator proper credit. Thanks!
This year I’ve decided to have my AP Physics C students (15) make screencasts explaining the workings of and reasonings behind their VPython programs. I got the idea from college physics professor Andy Runquist, who makes his students do similar screencasts for their Mathematica assignments. What I like about screencasting is that it gives added insight into which students understand the physics and the coding of their programs and which do not.
We’ll be using Screencast-o-matic because it is easy to use and it’s web-based (no software to download and install). Another reason is because Screencast-o-matic allows for “open submissions” — i.e., students can record and submit their screencasts directly to a designated channel without having to create an account or upload their video to YouTube. Which is great because all the screencasts will be in one place and I don’t have to worry about getting/managing links from students.
To help students with screencasting, I’ve made a tutorial video, along with examples of good and bad screencasts.
