Corner Refractor - "Figuring Physics" in the May TPT

Paul Hewitt (author, Conceptual Physics) contributes a "Hewitt Drewitt" physics cartoon puzzle to each issue of the American Association of Physics Teachers magazine/journal, the aptly titled The Physics Teacher.

This month's "Figuring Physics" a refraction puzzle that came to me last year while retooling an interactive classroom lesson.

Corner Refractor (PDF)

Hewitt would implore you to wait before getting to the solution. And all the "Figuring Physics" puzzles are intended as "Next Time Questions," meaning you give them to students one day, and don't provide answers until next time, no matter how compellingly students beg.

Corner Refractor - Solution (PDF)

I'm delighted whenever I can conjure something good enough for Paul Hewitt to use in the column. "Figuring Physics" requires the right balance of trickiness and accessibility, novelty and familiarity. They're not easy to write.

If you've got one, send it in! He's always keen to have more.

Need some inspiration? Or just looking for more where this one came from?

Hewitt's Next-Time Question Archive at Arbor Scientific.

Pixel Peeping - a new PhET activity

PTSOS colleague, Dan Burns, has his students look at pixels through a small, powerful magnifier. Five years after he shared this idea at a PTSOS workshop, I finally figured out a way to make this work for my own students. (I'm kinda slow.)

It involves the use of PhET's Color Vision sim in addition to a magnifier.



Having run a few early drafts in class, I will warn you that you'll hear many involuntary expletives of amazement while students undertake this investigation. They've been looking at displays all their lives. And they never knew what was going on at the microscopic level.

I'm always a fan of activities that get even the most jaded, "been there, done that" high school teenager to revert to the sense of wonder they had in elementary school. Even if only for a few moments. So I can recommend this one without hesitation.

Pixel Peeping at PhET

Zombie Marie Curie is here!

and well-intentioned marginalizers gonna have some 'splainin' to do.

Dig in! (Click the first panel to get the rest of the story.)

TAM 9 From Outer Space

This is your friendly reminder to get it in gear if you want to go to this year's premiere celebration of science, skepticism, and critical thinking. The Amaz!ng Meeting 2011 (TAM 9) will be held July 14-17 at the South Point Hotel, Casino, and Spa in Las Vegas.

The luminaries scheduled to appear include Bill Nye (The Science Guy), Mythbuster Adam Savage, Neil deGrasse Tyson, Lawrence Krauss, Richard Dawkins, Michael Shermer, Phil Plait, PZ Myers, magicians Penn & Teller and Banachek, Skepics' Guide to the Universe and Skepticality talents, awesome Aussies Karen Stollznow and Richard Saunders, Brit-wit Richard Wiseman, entertainer George Hrab, and many, many, many more.

It's difficult to describe this conference beyond the term, "Amazing." I will say that I've been to TAMs 2, 3, 4, 5, 6, 7, and 8, and that I intend to go as long as
a. they are held and
b. I am alive.

For what it's worth, I do not make that claim regarding any other conference or meeting series that I attend other than TAM.

The attendance for TAM has grown every year (and throughout the Great Recession) because if you're anything like me, you get hooked at your first TAM and never miss another. Best. Addiction. Ever.

The Amaz!ng Meeting 2011: TAM 9 From Outer Space!

Shine a Light

The good people at PhET have produced a sim called "Photoelectric Effect." As they describe it, "See how light knocks electrons off a metal target, and recreate the experiment that spawned the field of quantum mechanics."

I wrote an activity to go with it. In honor of Paul Hewitt's affection for The Rolling Stones (and because it's the right title for the activity), I called it "Shine a Light."

As of this post, I haven't uploaded the instructor's notes and answers to questions. But for the adventurous among you, I think you'll find the activity very straight forward.

Shine a Light PhET activity page.

The end of the world is coming (again)

Excuse me while I don't stifle a yawn.

Harold Camping has pegged May 21, 2011, as the day that good Christians will be raptured and Judgment will begin. "It is going to happen, There is no Plan B," he says. Camping is the 89-year old founder of Family Radio, a $100,000,000 media network. Family Radio's financial situation improves as Camping's followers surrender their personal wealth to his empire. He assures them money will have no value on May 22.

Camping, like pretty much anyone else who predicts the end of the world these days, is
1. a self-styled "Christian" who has personally cracked the Bible's secret code to learn the date of The End.
2. confident that he'll be afloat during the Rapture.
3. a veteran of at least one End of the World prediction that failed.

Oh yes, he wrote not one, but two voluminous tomes (1994? and Are You Ready?) declaring that the Rapture and Judgment would commence in 1994. In conceding the obvious, he confessed to not looking into the Book of Jeremiah, which is apparently a very important source of end-times data. Last time he was wrong; this time he'll be right. No really!

The Family Radio army is on the march, spreading "The Word." What should we expect on Judgment Day? Camping's followers say that "starting in the Pacific Rim at around the 6 p.m. local time hour, in each time zone, there will be a great earthquake, such as has never been in the history of the Earth." Sounds frightening.

I decided this is teachable moment. There is no end-of-the-world theory so wacky that hoards of followers won't climb on board. But I'm not keen to have any of my students jump on those bandwagons.

So I prepared a poster listing some of the most prominent end-of-the-world. About 50 of them, on a 17" x 22" poster. (This kind of thing happens when you can make 17" x 22" prints. Anyway, I think it looks pretty good. I'll post it for the May 21 End of the World. I'll post it again for the December 21, 2012 End of the World. And I'll post it for any other Ends of the World that happen between or beyond those dates.

I worried that taking on Camping and Family Radio would give offense to my Christian students, but was assured (from all corners) that it would not. He ranks up there with the Westboro Baptists for giving Christians a bad image. Delusional nut cases who profit by spreading fear do not qualify for "tolerance." They qualify for scrutiny and example-making. Which is not to say derision and mockery are off the table.

THE END OF THE WORLD! ...has happened before (many times). (PDF, native at 17" x 22")

National Public Radio's story on the May 21, 2011 end of the world story.

Harold Camping's Family Radio.com

Connecting the Dots

As mentioned in a previous post, a PTSOS participant alerted me to the prospect of constructing a wave machine with Gummy Bears.

I was intrigued enough to give it a shot.

The inertial candies used in the original were the UK-specific Jelly Babies. Sure, we have Gummy Bears (and Gummi Bears) here in the states. But their masses are significantly less than those of the Jelly Babies.

A Jelly Baby packs 6 grams of gelatinous sugar into its plump, opaque body. A Gummy Bear gets by with a mere 2.5 grams of see-through, rubbery gel. It could be eaten by a Swedish Fish for a twist of confectionary irony.

I opted for Dots, a product of the Tootsie corporation. They're nearly 4 grams each. (I didn't know the actual mass of a Jelly Baby until after our in-class project).

My OCD tendencies required that step 1 of the project was to sort the five flavors/colors of Dots. The Wikipedia entry for Dots says that Tootsie claims all flavors are produced in equal amounts. We found that cherry red outnumbered any other flavor by more than 2-to-1.

The rest of the project is represented fairly well in the video I produced and uploaded to YouTube. (Curiously, I produced the video in Apple's Keynote, which allowed me to include some nice construction animations.)



UPDATE 3/26/2022: Connect the Dots [Lab] at Teachers Pay Teachers

ExploratoRio 2011 photo prelims

While hosting ExploratoRio, I try to snap a photo or two. That's probably a bad idea, since there are so many mini-crises I should be resolving. And I should spend more time greeting the visiting teachers and chaperones. And I have students who are supposed to be snapping pics all day long. But I can't help myself.

Here is a preliminary set to show for our efforts until the student photos comes in. With any luck, they will have minded shooting details better than I did.

But for now...



Oh, we did have 14 elementary classes visit from 8:30am-12:30pm. That translates to about 400 students (in addition to my 150). It's not a trivial matter for teachers to coordinate a field trip to come visit us, so it was especially delightful to see so many young investigators throughout the day.

The rooms were rockin' all day. The little ones were impossibly cute and overflowing with unrestrained enthusiasm as they pulled each other over to their favorite exhibits. Their unvarnished expressions of wonder and joy could make you cry.

ExploratoRio is coming (and I may try something new)

UPDATE: ExploratoRio evening program has been bumped up. It will run from 6:30pm to 8:00pm. 
It seemed so far off when we began preparations six weeks ago, but April 6 is rapidly approaching. That's the date of Open House, so that's the date of ExploratoRio 2011.

Student exhibitors have been building and researching their exhibits. Elementary class hosts have booked every visitation slot on the schedule; we should have young explorers visiting from 8:30am to 12:30pm.

I spent a few hours in the classroom over the weekend to beat back the entropy of of the school year. I was also inspired to develop a new "snack." Over the years I have developed a handful of ExploratoRio Science Snacks for students to choose from, in addition to the Exploratorium Science Snacks published in Square Wheels and the original Exploratorium Science Snackbook.

My new snack is "Wristbandits," inspired by the recent renaming of Sacramento's ARCO Arena to Power Balance Pavilion. Earlier this year, I developed an in-class lesson exposing the pseudo-scientific hoax that the highly-popular wristbands (with or without holograms) represent.

With the onset of ExploratoRio, I thought it would be nice to have an exhibit exposing the methodology of the fraudulent demonstrations used to promote the bracelets. Once I was struck with an appropriate title, it was on.

All I need now is to draft some student exhibitors to present it. In any case, we set up tomorrow after school, clearing the room from 3-5pm and installing the exhibits from 5-6pm. ExploratoRio runs from 7:50am-12:30pm and 7:00pm-8:30pm 6:30pm-8:00pm Wednesday. By 10:00pm 9:00pm Wednesday, it will be as if nothing ever happened: the classroom will be a classroom again, ready for regular use on Thursday morning.

My HS Physics to California Physics Alignment

In the residue of the school's recent WASC evaluation process, there is an interest in increased "transparency." There was a sense that we're doing well as far as instructional outcomes go, but that it's difficult for outside parties—themselves not a part of the school's community—to see how we do it. And it's been decided that that is something of importance.

Action plans are being formulated. Benchmarking and data-generation are priorities. Interest is keen in collecting data to demonstrate student attainment of the school's Expected Schoolwide Learning Results. [I would have linked to the ESLRs, but either my google-fu is poor or the school's website doesn't offer the document online. And that seems unlikely since each classroom was provided with a 24" x 36" laminated copy.]

Curiously, those ESLRs were fashioned to represent broad, longitudinal goals to be attained over the course of a student's four-year tenure at the school. And that's what ESLRs are supposed to be. Though I travel far and wide, I have never seen data-collection instruments designed to show ESLR attainment.

But ever the student, I'm eager to see effective examples such instruments. And even more eager to see the spreadsheets of the meaningful data generated by such instruments. And the remedial measures that will be enacted to ensure that each graduate will have ESLR data to support their right to walk at commencement. (That in addition to CAHSEE results and adequate academic performance and attendance records.)

To better serve outsiders looking in—now that I'm coming to terms with their priority as stakeholders—I have modified my Physics 1 unit schedules to include actual text of the California 9-12 Physics Standards covered in each unit of study.

And I'm hoping that this alignment document will bring joy to someone who might find value in it. Anything I might have accomplished in the time required to prepare the document will pale in comparison to the fulfillment and reassurance it will provide to outside investigators curious to the methods of our campus.

I am nothing if not a team player.