What's with the "hairy" lightning?

Look closely at the discharge path of this giant van de Graaff generator. The full image is here. The generator dome is on the right, the discharge sphere is to the left. The primary discharge path is nicely bright. But look at the faint ("darker") blue spray. It follows the direct path where the discharge drops down to make the U-shaped part of the path. But there are other "hairs," too. Is that a clue as to the sign of the charge on the main dome? What do you think?

There are more discharge images here.

Vacuum Gun Still

The kids (and by that, I mean physics teachers age 18-108) have yet to tire of the ping pong vacuum gun. Monday evening's AAPT demo show included one. I like this particular still. Look carefully; the ping pong ball emerged from the PVC tube at the far left and has passed through the first can. It is beginning to pass through the second can. The third can is, as yet, unaware.

The full image is here.

Sunday Sunny Syracuse

Sunday may be the best day of the conference.

A workshop in the morning covered a significant portion of cognitive research in physics education.

At lunch, I was able to get Al bartlett's quick review of Al Gore's An Inconvenient Truth. Bartlett was generally pleased with the presentation, but referred to it as An Incomplete Truth. Bartlett was disappointed by the omission of population growth as the most significant ultimate cause of global warming.

An afternoon workshop was a brief immersion into a robust family of physics simulations.

Dinner was a disappointment. Dorm food in all its dorm food splendor. I mean, "wow!" I had allowed myself to repress the memories. The trick is to enjoy a hearty breakfast and a heavy lunch so that dinner is irrelevant.

The High School Share-a-thon was next, and a number of groovy demos were show. There are photos here. The photos do some justice to the demos, but they fail to capture the bad puns and other clever banter. To get that, you had to be there.

I'd write more, but there's stuff going on!

My AAPT Syracuse Photo Album

...is here: http://phyz.smugmug.com/gallery/1699477

Included are photos from Sunday's High School Shar-a-thon and Monday's Demonstration Show.

Syracuse Saturday Sans Sunshine

Friday was flyday and in only three flights, I got from Sactown to Syracuse. Saturday was a rain day in Syracuse. Steady, warm, and... steady. Lots of soaked physics teachers around campus and brisk umbrella sales in the bookstore. I thought to bring my raincoat and an umbrella, so I was good to go.

I spent the day with Dewey Dykstra, a physics education rock star. I attended his optics workshop in 1989; to this day I have never seen a better set of inquiry-based labs on reflection, refraction, pinholes, and lenses. Upon completion of the pinholes-lens sequence, you really had an understanding of lenses, rather than a simple ability to draw ray diagrams and "get the right answer" to thin-lens equation problems.

Today's workshop focused on learning theory with an emphasis on elicitation of student conceptions. I'll wait while you savor my clever use of the term "focus." Some of the material was a bit heavy, but the point was how much you can learn as a teacher through sequences of elicitations and discussions. Dewey is a master of this, and he's a genious when it comes to uncovering misconceptions then devising activities that confront those misconceptions. Very groovy stuff.

I also got a kick out the tangents we were able to get him on. Hall's (of The Hall Effect) writings on the nature of the electric fluid, how he groups his students for lab work, etc. I'd pay for a workshop just to hear more of his stories!

Anyway, I didn't miss the 110F that Sacramento was enduring.

"Your mother and I were talking...

We see that you signed up for physics next semester. Hey, that's great; good for you!

The thing is, we've been keeping track of the latest research in gender-based differences in cognitive abilities, and it turns out physics is more of a "guy class." More males than females scored exceptionally well on a math test given in an enrichment course for high-achieving students at Johns Hopkins, and other studies show that boys often outperform girls in tests of spatial visualization.

So we were thinking you might want to drop physics and sign up for that communications class. The research says girls excel in verbal communication skills.

We only want what's best for you."

I'll give you moment to shake that off. You know, there's no prouder moment for a blog author than when he or she can ask colleagues, "So, have you been following that lively internet discussion on my blog?" I jest. It has been suggested that "lively internet discussion" is an oxymoron of sorts. But I digress.

Amidst the gender-based cognitive differences discussion going on at this blog, I've seen many calls for "let the research be done!" This sentiment follows a noted Ben Franklin quote, "Let the experiment be made." Then again, none of us would have to stretch our imagination too much to envision experiments that shouldn't be made.

What I haven't seen is anyone stepping up to tell me what the point would be. So let me start the song and invite anyone to chime in.

The research results are in. Gender-based cognitive differences have been identified. As a result of these findings, we're now going to... OK, that's where I got nothin'. Somebody go ahead and pick it up from here. (Kindly keep in mind that all such "findings" so far have been insignificant when compared to individual variations within a given gender.) I hope no one suggests parents start having the discussion at the top of this post.

Anyway, tell me the what the application of the research results might be. I am eager to learn.

Please disregard California

In 1985, California stared down Texas over the inclusion of the term "evolution" in science books. Texas' Mel and Norma Gabler were trying to establish Texas as an evolution-free zone. Publishers were warned that books containing the word "evolution" would not be adopted in the Lone Star State. California's Bill Honig promptly fired back: books that excluded evolution would not be adopted in the Golden State. Thus the nation's number one textbook market successfully quashed the wrong-headed notions of the number two market.

When I read about this clash, I decided I could work in a state like California. By the autumn of the next year, I had the job that I hold to this day. I love my chosen state and I love my chosen profession. I bear no body art, but if I were ever to inject ink into the epidermis of my derriere, it might say "California Physics Teacher."

But now I go to national physics teachers meetings with some embarrassment. When I tell my fellow high school physics teachers from around the country that I'm from California, I'm also on the verge of an apology. While the Golden State was a leader on the evolution front, it plays a rather different role in terms of Physics First (PF, the movement to teach physics at ninth grade, chemistry at tenth, and biology at eleventh).

My state has banished PF from public schools.

The No Child Left Behind legislation demands each state test its students in various subjects at various grade levels. One requirement is a science test to be administered to all students at a specific, senior high grade level (grade 10, 11, or 12). I serve on an panel that advises the State Board of Education on issues of assessment. It's called the Assessment Review Panel. The SBE solicited the ARP's opinion, then decided the implementation of NCLB would be a test of all grade 10 students in life science.

That's how the SBE killed PF with NCLB. With schools testing all grade 10 students in life science, PF students wouldn't likely perform well. The test would come before their study of high school biology. Of course, you could try to reason with your principal: "Hey, I've got this great idea for our science sequence. The students will learn science better, but our NCLB test scores will drop." Look, I made a funny!

What makes me groan even louder about this mess is that I was a player (albeit a small one) in the decision-making process. Clearly, the SBE did not implement NCLB as I would have liked, but my arguments failed to carry the day.

To my colleagues in private schools and to those in other states, I truly wish you well in your attempts to implement PF in your schools. There is merit to the approach of a physics-chemistry-biology sequence. So for this issue, pretend like California's not even here.

Everybody... Jump!

The Bad Astronomer is a never-ending fount of facts and funnies. He and I attended Michigan at the same time and had a friend in common, though we never met in Ann Arbor. Whenever you hear some wacko astronomy story in the news, proceed directly to www.BadAstronomy.com for the real story.

He's posted a note about World Jump Day. What, it wasn't on your calendar? C'mon, basic physics tells us that if we can get 600 million people to jump at the same time, we can move the earth into a different orbit. If coordinated correctly, we can move the earth farther from the sun and save ourselves from the fate that global warming has in store.

Or not.

How many times do we see evidence that someone studied physics enough to learn of some classic problems or sketches of basic principles, but they didn't study thoroughly enough to internalize the solutions or consequences of the principles? Nevertheless, they go on to organize something like World Jump Day or design the next perpetual-motion machine.

Anyway, there's a hip lesson to be made from this kind of thing. A lesson that is especially groovy because it invokes real physics and throws in a splash of critical thinking as well.

Gender imbalances and horror stories

I had the good fortune of seeing Australian guitar sensation Tommy Emmanuel perform in Berkeley last night. As if that weren't enough, I was sitting next to Karen Stollznow a tireless Australian skeptic, author, and linguist (and creator of the pope-tart).

We had a chance to chat here and there, and I cringed when she recounted her high school physics horror story. Not because I hadn't hear such accounts before. I am well aware of the harsh treatment of girls and women in physics courses in high school and college. I wrote my master's thesis on the gender imbalance in physics education. So the novelty of hearing about the mistreatment, alienation, and marginalization of girls in high school physics classes is gone. OK, the stories still make me cringe because of the stupidity and shortsightedness of the teachers involved.

I cringed at this story because my Australian skeptic friend was not old enough to have been in high school physics in the 1950s or 60s when a girl in a physics class was a rarity. She was young enough to let me know this kind of damaging BS is still going on. Will these backward geezers never retire? Or at least realize that the 50s are over?

Anyway, my gender imbalance sensibilities were no-doubt heightened by the recent re-examination of the 2003 American Council of Education regarding gender imbalance on the college campus. In 2003, the council found that men were lagging behind women in terms of college enrollment. The re-examination finds the gap isn't quite what it was originally thought to be.

Women certainly don't outpace men in the physics and engineering programs. And while we would like to believe that male bias in physics education is a thing of the past, a 1998 study tells a different tale. In it, the authors concluded that males had a better sense of simple ciruits than females. The evidence? When males incorrectly wired a battery and bulb circuit, they created a short circuit. When females incorrectly wired a battery and bulb circuit, they created an open circuit. Of course, neither circuit was successful in lighting the bulb. But the males' short circuit succeeded in destroying the battery, and was deemed the superior incorrect solution.

So there you have it: the smoking gun! Larry Summers was right all along! I don't know why girls even sign up for physics...

AP Physics is a second-year course

About ten years ago, I began plotting a significant change in the physics curriculum at my school. My plan was to change our AP Physics B course from a first-year course to a second-year course. The reasons for this change are detailed here.

Briefly, AP Physics (B or C) is a second-year course. All AP sciences are second-year courses. Your colleagues who teach AP Biology or AP Chemistry wouldn't think of teaching their courses to first-year students. The College Board describes AP Physics as a second-year course.

Still though, many schools offer AP Physics as a first-year course. Why? The most frequently cited reason I've heard is that there's not enough time for students to take a two-year physics sequence. Well, there's not enough time for students to take a two-year biology or chemistry sequence, either. Nevertheless, those courses remain as second-year offerings.

We should encourage our most enthusiastic and gifted science students to complete a year of biology, chemistry, and physics, followed by an AP science course of their choosing.

The most successful first-year AP Physics teachers I've had contact with confess they do not do labs in their classes. What? A science class--a science class for the best and the brightest--with no labs? They assure me that they do labs--after the AP exam. The AP exam happens the second week in May. Most schools are out the first week of June. At my school, the last week and a half of school are devoted to staggered final exam schedule. So there's not much of a window, and I would suggest students are not at their best in that particular window.

Later I'll post some info about the consequences this change at my school.

The Blog of Phyz?

I noticed two things recently.
1. I couldn't find a blog relating to issues of high school physics instruction.
2. I'm on summer vacation.
Hence this blog.

By the time I first started posting a website (now found at phyz.org), I was an nine-year veteran of the physics classroom. I created a site because I thought it could be a useful vehicle for sharing information for my students, their parents, and for other physics teachers. That and I was curious about HTML, web page creation and posting. No better way to learn than to have a practical project at hand.

That was 1995. By 1997, the Phyz web site was fairly well fleshed out. And it was serving its purpose as an information portal. A few years later, I wanted to learn about Portable Document Format, so I turned my hand-crafted curriculum materials into PDFs and posted them on the site. With each step of its evolution, the site became more useful to its intended audience. And I'm happy to see many other teachers starting to create sites for their own classes.

Now I'm curious about the ins and outs of blogs. This one is intended as a conversation among physics educators and those concerned about physics instruction at the high school level. At its inception, I do not know how frequently I will update it or if eyes other than my own will see the words it contains.

AAPT Syracuse or Bust!

The Summer Meeting of the American Association of Physics Teachers is set for July 22-26 at Syracuse University in New York. My registration is in, my deluxe dorm-room accommodations are reserved, and the flights are booked.

This conference is a great chance to meet physics teachers from throughout the land and get a sense of what the hot topics are outside one's own neighborhood. I'm scheduled to attend a few workshops on the first two days; these are usually the best part of the meeting. There are activities for conferees from 8:00am through 10:00pm most days; you have to sneak off to effectively socialize.

While it is true that conferees are involved in physics education, it is not true that they are all males over 40 (age OR waist measurement). That bit of misinformation is both irresponsible and erroneous. Seriously!

I'm looking forward to a few days of learning and laughter among my colleagues. Or as the kids would say, "chillin' wit my phyz homies." Yeah, that's just wrong.