WulfTheTeacher

Monday, October 31, 2005

Quote of the Day

"In physics, it takes three laws to explain 99% of the data; in finance, it takes more than 99 laws to explain about 3%."
Andrew Lo

Sunday, October 30, 2005

Counting Curse Words?

I don't have Chuck Shepherd's "News of the Weird" as one of my daily news sources, but every once in a while I check in on him and find a real gem. The latest installment quotes the Daily Mail for the following story:
At the Weavers School in Wellingborough, England, teachers were told in August to tolerate 15- and 16-year-old students' cussing, even the "f word," at least up to five times per class. According to London's Daily Mail, the teachers were to merely keep a count of the words on the board, which the school believes shows tolerance for occasional bad language, but which more cynical teachers and parents believe will encourage the students to max out usage in each class.


I am thinking, No. I didn't tolerate that when teaching at the university level, and I certainly wouldnt' from high schoolers. Heck, I put a damper on it when I taught in the navy. If you can't curse like a sailor there, you certainly can't in my classroom. This is plain ridiculous - thus, I ridicule it.

Vector Torture

Note to myself for next year:

My physics courses generally start with basic definitions and equations of the terms of motion (like velocity and acceleration) so the students can describe how an object is moving.
From there we move into Newton's laws, with which a student can describe why an object is moving.

Then comes the fiasco of applying this knowledge in more than one dimension at a time. Vector addition is very difficult for these students. Even in my honors classes, only half of the students have had trigonometry prior to my class - I believe it is a corequisite course - so students are overwhelmed with the number of equations and relationships they have to use.

"I don't get it."
"What's the x component?"
"Wait... last time you used cosine, so why are you using sine here?"
"What are we trying to find, anyway?"
"I added the vertical distance to 9.8, because that's vertical too."

I think next year I will spend the first week or two introducing our use of trigonometry without any discussion of movement. If a line segment is placed on a graph from the origin to the point (x, y), can we find the horizontal component, the vertical component, the angle? Of course we can. And once they think of that process as a mathematical process - one of geometry, not of physics and motion - I suspect it will all fall into place more quickly.

I'll let you know next year.

Saturday, October 29, 2005

Teach Integrity

Any good scientist knows it is more important to record one's observations in the laboratory than to record what was expected but did not happen. It is a constant struggle to convey this message in the classroom. Students spend their entire schoolday looking for the "right answer" - usually meaning the one that will get parents and teachers off their backs so they can get to the business of doing what interests them. And is it so different in the real world?

M.I.T. Dismisses a Researcher, Saying He Fabricated Some Data

Sigh. I emphasize to my students that if their data is grossly wrong, but they are able to record it properly and explain why, then they are on track for a good grade. I have had students get a 100% on a lab assignment despite having an experimental error of more than an order of magnitude. If a student is able to sit down afterwards and figure out why the expected results were not achieved, and especially if they can explain a better procedure or setup for investigating the topic in question, then clearly that student deserves a superior mark. That student is a good scientist.

Our school has a writing initiative (to improve scores on standardized tests), and every teacher is required to give at least one writing assessment per quarter. Many teachers have an essay on their test and count that. Some assign the work as homework despite the fact that it is supposed to be done in a timed setting, like the standardized tests are. Personally, I like to get the students a little off-topic... for example, get them writing about ethics instead of the momentum chapter we are covering. I think this NY Times article on Dr. Luk Van Parijs may be the prompt for their next assignment.

Sunday, October 23, 2005

Technological Failures

I have fallen way behind my intended pace of at least three posts a week. I blame technology.

My school district is one that has been in the news for years, because we issue laptops to all students in high school and middle school. Initially these were iBooks, but the district made a very popular switch to the Dell Inspiron 600M this year (at least for the high schools - the Apple contract with the middle schools ends this year, and it is still not known which platform the county will choose for the next four years of middle schoolers).


There was some negative press about ditching the iBooks after a 4 year initiative. Well, no, there was some negative press about the stampede that occurred when the district offered the old student iBooks at $50 each.

But the public showed little concern about any glitches with the platform shift. Teachers and students were largely enamored with the new Windows machines, too, making naysayers look like the Cult of Mac - you know the type.

So now we have these new machines, and the Dells are for the most part faster machines than the iBooks were, and they have MS Office instead of Apple Works, which makes it easier for most people to get anything done. But they didn't manage to put on every last little bit of software that would be needed by every last little teacher, including the software for the PASCO probeware my school purchased over the last few years. We have a full lab set of motion sensors and force sensors for mechanics labs, plus an assortment of probeware for temperature, absolute pressure, sound level, light intensity, magnetic field intensity, and probably some other things I can't remember off the top of my head.

In other words, after the school spent a few thousand dollars on making our physics labs easier to do and easier to understand, the district took away our ability to use the equipment. I know it was not intentional or malicious, and frankly everybody is very sympathetic and concerned, but that doesn't change the fact that right now my students in the Class of 2005 are doing labs that are no more technologically advanced than those I did when I took the class 15 years ago. What's the point in having a laptop in the science classroom if you can't use probeware? It is very frustrating for me, because the last two years of probeware were such an improvement over having students plot position vs time by hand, or use spring scales and stop watches, with their great capacity for inaccuracy and error.

In fact, I have been spending many extra hours retrofitting all of my lab documents to the technologies of 1950... leaving very little time to sit here and blog about the teaching techniques that would make life easier for science teachers everywhere. Suffice it to say that I am a member of the Cult of Probeware. As the year progresses, I will share more of my experiences about using probeware to teach, both at the high school level and university (we used LoggerPro and video capture there, and I was hoping to start incorporating those technologies this year, but no dice - maybe next year).

Incidentally, I have seen Vernier probeware demonstrated, and I can't really see any difference between Vernier and Pasco. If you start to incorporate either into your science classroom and you have the appropriate software available, you will find that students learn more, and faster.

Friday, October 14, 2005

What do the Chinese call their astronauts?

Shenzhou-6 is China's first multi-manned and multi-day spaceflight (see here, here), and is now entering its third day in orbit.

My students were completely unaware of it. Most of them were unaware of the fact that the Chinese had ever been to space. None were aware that there is a new space race brewing, which may be bad for somebody politically, but which should be good for science educators.

Here is what my students know about space flight, in general:
- The Russians launched Sputnik and it was a big deal.
- The Russians put a man in space before the U.S.
- The Russians put animals in space, as well.
- John Glenn was an astronaut.
- The Americans did finally surpass Soviet achievements.
- The Americans landed on the moon (this is contested by approximately a third of my students, who believe that this has been proven to be a hoax. Proven!)
- "Apollo 13" is based on a real NASA mission.
- There was a shuttle that blew up on liftoff, in an unknown year. (One student even knew that a O-ring failed, though he was surprised to learn what an O-ring is, and how small one is. After I learned that they didn't know much about this, we watched streaming video of the Challenger, and many students claim never to have seen it before. I find this amazing, but I am sure some of you will find it amazing that I was born after the last lunar landing.)
- There was a shuttle that blew up on reentry a few years ago. Given a few seconds, they were able to recall that it was the Columbia. They had a vague understanding that foam cracked the wing. There was a sense that a coverup may have been involved on this catastrophe, as well.

Remember, these are 16-18 year olds in public schools in America. I was glad to see the things that were known by most, and I am endeavoring to fill in the gaps. The following is a very incomplete list of things they do not know about space flight, just based on the last week's worth of conversation:

- Anything about the X-prize, except that "that British guy who owns Virgin" is involved in a deal to commercialize space flight. A great discussion ensued about whether it is worth $200,000 to buy 2 half hour flights.
- Dennis Tito, Mark Shuttleworth, Gregory Olsen.
- Anything about nations other than the USA and USSR putting anything into space, with the exception of students who were of the same nationality as an astronaut they were aware of (Indian, Israeli, Japanese).
- ISS ("Do you mean there are people in orbit right now, on that thing?")
- the altitude at which things orbit.

I shared J-Track with AP today, and they were wonderfully impressed, as am I every time I check that thing out (JAVA applet 3-D plot showing the position of over 500 satellites in real time). The other classes may see it on Monday... technology pending. More about that in the next post.

Wednesday, October 05, 2005

SpaceShipOne on Display at Smithsonian's National Air and Space Museum

SpaceShipOne was formally donated to the Smithsonian in a ceremony in Washington D.C. today. It now hangs between Charles Lindbergh's Spirit of St. Louis and Chuck Yeager's Bell X-1.


Burt Rutan and Paul Allen were on hand at the ceremony. If you don't know what SpaceShipOne is and why it belongs in the NASM, consider this:
Like many space entrepreneurs, Rutan thinks the private sector can do what NASA cannot: inspire tomorrow's astronauts and scientists by offering them the real promise of a trip to space.
There are signs that SpaceShipOne's historic suborbital flights marked the dawn of a new space age.
Of the 26 teams that entered the Ansari X Prize competition, 10 are now viable companies, according to Ian Murphy, spokesman for the prize's successor, the X Prize Cup.
Rutan has a deal with British entrepreneur Richard Branson, chairman of the Virgin Group, to build a fleet of five spacecraft. The new company, Virgin Galactic, will take passengers on 2 1/2-hour trips into space for $200,000 each.

Tuesday, October 04, 2005

Nobel Prize Time

Wow, more than a week since my last post. Sometimes, it's hard to find time even to sleep or grade papers.

If nothing else, I have to say I am always excited by the awarding of the Nobel Prizes. Isn't everyone? I have been called a geek for much less, I assure you.

Early in the schoolyear, we always have to talk to science students about the precision of our lab equipment (or lack thereof). How accurate are the scales, meter sticks, etc? What uncertainty will this create in your measurements? How many significant figures do you have in this measurement?

Conveniently, we can refer back to these conversations when discussing this year's Nobel Prize winning research:

The Royal Swedish Academy of Sciences awarded the prize to Roy Glauber, John Hall and Germany's Theodor Haensch for studying light and harnessing lasers to create a "measuring stick" to gauge frequencies with extreme precision.
"We get most of our knowledge of the world around us through light," said the Academy, calling optics "the physicists' tool for dealing with light phenomena."

The winning trio's research answered such questions as how candle light differs from laser beams in a CD player and how light can measure time more accurately than an atomic clock.

"All three of them deserve the prize," said Peter Rodgers, editor of Physics World magazine. "The general area of quantum optics and lasers is an area in which there has been a lot of progress in recent years. This prize reflects well on progress in that area."

Haensch used even-spaced laser pulses "like the teeth of a comb or the marks on a ruler" to determine the value of frequencies and Hall refined this technique.

"One of the best applications is to test whether what we teach in physics is true or just approximately true," he said.