Sunday, October 19, 2008

PTSOS1 Afterlinks 08

Here are some afterthoughts and links related to the first PTSOS New Teacher Workshop in Sacramento, held at Rio Americano High School Saturday, October 18. Most PTSOSers know about,, the PTSOS Yahoo Group, and, but we blasted through some other resources as well. We cover a lot of ground at PTSOS New Teacher Workshops, so here's a list of some of the specifics that might have sneaked past you.

Steve Keith demoed Vernier Software's student-friendly Logger Pro for physics data-plotting. Steve's also a fan of Arizona State University's Modeling Workshop. And he gets pretty good mileage out of Interactive Physics. I'm impressed with the potential of IP, but I'm disappointed that they no longer support the Macintosh platform.

I mentioned ripping video from YouTube on the Mac OS X platform. In the ever-changing world of Internet applications, sometimes it's best to simply use your Google-fu. I'm currently using TubeTV (with QuickTime plug-in, Perian, installed). But it looks like there are other things out there, such as YouTube Grabber and TubeSock. If you try them, let us know how it goes.

We looked at some video clips from Physics Cinema Classics. Specifically, the "Cannonball"-related clips. I haven't been able to relocate those on YouTube (they may have been removed per copyright issues), but here's a nice substitute (in keeping with Steve Keith's advice to work cars into the curriculum). With QuickTime (free for Macs and PCs), you can step through the video, frame by frame.

In addition to the Tumble Buggy (with Keith Industries' custom battery slug), Drilled Balls, rare dart guns, and Geyser Tubes included in your Goodie Bags, we saw ideas for using a Newton's Cradle, Visual Accelerometers (and the old-school liquid accelerometer), Introductory Dynamics System, Rotating Platform. Steve demoed Falling Rhythm.

We also talked about skepticism and critical thinking. I've got a page of mini-lessons in this area. Here's a nice resource on spoon bending. It includes video of the world record spoon bending from The Amazing Meeting 6 this past summer in Las Vegas. There's an excellent episode of Nova devoted to this topics as well: James Randi's Secrets of the Psychics.

The existence of Released Test Questions from California's Physics Content Standards Test was news to some. I'll print a set for PTSOS2 participants. By then, there should be 15 more questions in the set.

Oh, and we strongly recommend attending local NCNAAPT meetings and joining the American Association of Physics Teachers (The Physics Teacher, AAPT's journal, is worth the annual dues).

Sunday, October 12, 2008

Letting go of Newtonian mechanics

I'm finishing my unit on uniform circular motion and gravity. We'll test on that this week and move on to momentum.

In the rearview? Preliminaries, motion and inertia, force and interaction. That is, kinematics and Newton's laws. By week's end, I'll be done with the first of California's 9-12 Physics Standard Sets (Motion and Forces) and started on the second (Conservation of Energy and Momentum).

I say this as someone who will not make it through all California's Physics Standards by the time the Physics CST strikes in April.

And I say it as someone who imagines there are many California high school physics teachers out there not as far into the curriculum in mid-October. I know we all love our mechanics topics and could spend the entire year deeply immersed in them, but that typically requires sacrificing rainbows and blue skies.

It's worth mentioning The Hewitt Doctrine: "Don't Let Kinematics Become a Black Hole of Physics Instruction." Conceptual Physics author, Paul Hewitt worries that we'll spend half the year working with ticker-tape timers and increasingly trickier graphical and algebraic kinematics puzzles, only to run out of time before giving students even the most rudimentary exposure to electricity, magnetism, optics, or many other fascinating topics in introductory physics.

Conscientious physics teachers fear that without a thorough understanding of motion and forces, students will not be able to grasp subsequent topics in physics. This turns out to not be the case. Very little of the sky falls if you move on from mechanics before it's fully fermented.

The deep understanding of kinematics and Newton's laws that most physics teachers obtained on their way out of college should not be expected of high school students in their first exposure to the topics. They don't all really need it.

I recommend letting it go and moving on.

If anything, students need more time with electricity and magnetism. These topics are very abstract, so lab work and slow development of concepts is called for. Of course, the year is finite (180ish days). If you're going to have a chance at E&M, you're going to have to get out of mechanics earlier.

Just a thought. Double your money back if the advice doesn't work for you.