In Science Classrooms, a Blast of Fresh O2
Maybe you’ve seen the television quiz show, “Are You Smarter Than a 5th Grader?” and will proudly attest that you are. But how might you stack up against the students in Faye Cascio’s ninth-grade physical science class? Consider the following problems:
1) You fall into a swiftly moving river and are in need of a flotational device. You see a life preserver bobbing three meters downstream of you and another one the same distance behind. Which preserver should you swim toward?
2) A bullet is fired into one end of a spiral tube. When it shoots out of the other end, and forgetting here about the effects of gravity, will the bullet follow a trajectory that (a) is a straight line; (b) begins as a slight curve in the same direction as the spiral tube before gradually straightening out; or (c) begins as a slight curve in the opposite direction of the tube before straightening out?
3) A plane flying into a headwind will have a lower speed, relative to the ground, than it would if it were flying through still air, while a plane traveling with the benefit of a brisk tailwind will have a comparatively greater ground speed. But what about a plane flying through a 90-degree crosswind, a breeze that is buffeting its body side-on? Will its ground speed be higher, lower or no different than it would be in unruffled skies?
The school year is still young, and so, too, is the Academy of Science, the almost sneakily rigorous high school magnet science program in Loudoun County, Va., of which Ms. Cascio’s physics class is a part. Yet already her freshmen students can not only ace exercises in Newtonian mechanics like the samples cited above, but they can also explain the reasoning behind every answer they give.
Many people wring their hands over the state of science education and point to the appalling performance of America’s students in international science and math competitions. Yet some of the direst noises about our nation’s scientific prospects may be premature. Far from rejecting challenging science courses, students seem to be embracing them.
This year, for example, the American Institute of Physics said that the percentage of high school students taking physics courses was at an all-time high, and that the number of bachelor’s degrees awarded in the subject had climbed by 31 percent since 2000. Moreover, there are a growing number of “magnet” or “gifted and talented” programs in secondary schools that emphasize science and math. While quality varies widely, and some observers worry that the tiny, competitive programs consume an outsized portion of a school’s budget, a visit to Ms. Cascio’s class and her students, who are not only gifted, talented and magnetic but hardworking, too, is almost enough to make you wish you were back in high school.
So, which life preserver to swim toward? It’s the same either way, just as it wouldn’t matter if you and the floating rings were in a pool on a cruise ship: the speed of the ship won’t affect how quickly you reach one ring or the other.
The path of the bullet as it emerges from its spiraling tube? Well, Newton’s second law, the famed law of inertia, insists that a body in motion will stay in motion unless something persuades it to do otherwise, and that includes directionality. With the elimination of the curving walls of the tube, nothing remains to deflect the bullet off an otherwise linear path: from the point of departure, it’s all a straight shot.
The plane’s ground speed in a crosswind? Ms. Cascio’s students will explain that it is greater than it would be in calm air, and with a few deft sketches of vectors and triangles, they will tell you by how much.
The students can articulate their reasoning because, for one thing, they have no choice. One recent morning, Ms. Cascio asked several students in succession to explain the logic of their answer to the same question — and, “Uh, yeah, I agree with Yasamin and Josh” just wouldn’t do.
“It’s called dipsticking,” Ms. Cascio said. “It’s really important to make sure the kids are picking this information up, and so I ask, Is this clear to you? Do you really understand it? and I won’t go on until I get a positive, satisfying answer.”
A bigger reason the students seemed to wear the material comfortably emerged when they pulled from the classroom closet genuine items of clothing: white lab coats. The Academy of Science is built on the principle of what its director, George Wolfe, calls inquiry-based learning. “I want them to learn to think like scientists,” he said, “rather than regurgitate facts.” From the moment they enter the program, students do experiments, lots of experiments. Not canned experiments, either, of the sort found in the average “science is fun!” book that spell out every step. Here, the students must design experiments themselves, which means they must learn essential lessons like how to ask questions in an answerable way, what’s your error bar, and, will you please just give me some data already.
Their natty new lab jackets shrugged into place, the students in Ms. Cascio’s physics class set out to demonstrate by experiment, in four four-person teams, the Newtonian verity that force equals mass times acceleration. One team proved hyperefficient, and within moments was catapulting ever more heavily weighted wheeled mini-carts along the tabletop and timing each run. Another team got bogged down debating whether their experimental design would work better with one long string or three short ones, until finally their teacher trilled, “Stop obsessing — let’s go!” A boy yearned for a pulley. Too bad, none available.
A mildly manic half-hour later, the data from the four teams were in and projected on an overhead slide for all to see. Calculators clicked as the young white coats computed the percentage of error in their collected findings, and, whoa, it was only 6.6 percent. “That’s phenomenal!” Ms. Cascio crowed. Think about all the things that could have thrown your experiments off course, she told the class — the low-tech equipment, friction from strings rubbing on stacked textbooks. “But even with that, look at how fabulous the results are,” she said. “You set up a great lab, and you should be proud.” It’s one thing to read about Isaac Newton and apples falling from a tree. It’s another to test his laws of motion and see how right they can be.
Ms. Cascio, 57, is a law of motion herself, a stylish dynamo whose voice retains the comforting vibrato of her natal Jersey City. As an undergraduate at Douglass College of Rutgers University, she studied molecular biology and planned to become a doctor, but while living in Greece she began teaching and fell in love with the profession, eventually earning master’s degrees in biology and education. With her decades of experience and a string of national teaching laurels, Ms. Cascio could easily have settled into rote mode, but instead she decided to join the fledgling Academy of Science, where, she admits, the pace can be grueling. “It takes a lot more time to teach inquiry than by plug and chug, by getting up in front of a class and lecturing by the book,” she said.
But how much more satisfying the nosy approach to knowing can be, and how amusing, too. In one biology class last year, for example, Ms. Cascio’s students acquainted themselves with the cell, the nucleus, DNA, proteins, evolution, taxonomy and other bold-faced biology concepts by analyzing meat and seafood products from the supermarket, discovering that, hey, the things that had been sold as scallops were actually pulverized trout pressed into scallop shapes.
Through its emphasis on Socratic parrying and creative laboratory work, the program could well serve as a model for remedying misconceptions. Nearly all scientists and educators agree that somehow, at some point during their pedagogical odyssey, most Americans get the wrong idea about what science is, and what it is not.
“Science is, or should be, about the world, not about science,” said Eugene Levy, a professor of physics and astronomy and the provost of Rice University. “But for too many students, science has been presented as a large series of manipulations that they rarely understand or connect to the reality around them.” If there is a message that he wants his students to take from his introductory science class, he said, “it is to grasp that the world is in fact understandable, that rational inquiry can lead to understanding, and that there’s rarely an excuse to say understanding is beyond them.”
In Ms. Cascio’s class, ignorance is always an excuse — to get out your lab coat. May I have a pulley this time?
1 comment:
Great teacher with the desire to make a difference each and every day.
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