Unlearning Bad Science
The news of the so-so performance in science by American students on the latest TIMSS assessment will be used by some to accelerate the expansion of the No Child Left Behind Act. But that federal law’s mandate for more science testing may actually make matters worse. It could lead to more rote teaching of material that’s easy to test on multiple-choice exams. It could lead to “dumbing down” the science curriculum, which will drive competent teachers either to distraction or to other occupations.
The larger picture isn’t much brighter. Congress has slashed funds that the National Science Foundation uses to improve science teaching, ever larger numbers of school districts are embracing “creation science” (typically under the guise of “intelligent design”), and, in the name of national security, the Bush administration is turning away bright foreign students who want to study science at our universities.
All of this is obscuring what may be a greater challenge—unlearning bad science.
Teacher Scott Byington likes to ask his science students at Cary Academy in North Carolina which organism has the most chromosomes per cell: mosquitoes, corn, broad beans, cats, or humans? The kids always pick humans, and they are correct, because we have 46 chromosomes, while cats have 38 and mosquitoes only 6. Then Byington expands the list to include horses, chickens, goldfish, and potatoes. Once again, his students confidently choose their own species. At that point, he tells them that even potatoes, with 48 chromosomes, beat us humans, and goldfish have 104 chromosomes, more than twice as many as humans.
Invariably, the students are stunned. How can they be less evolved than a potato? Or a horse? What Byington wants them to do is confront their assumptions, because he knows that in order for students to learn science, they first have to unlearn what they have assumed (in this case, the more chromosomes the better).
As children, we make all sorts of “common sense” assumptions about the ways the world works, which is a loose definition of science. “We have more brains than horses or potatoes do, so we must have more chromosomes,” or, “The sun makes us warm, it’s warm in summer, so the sun must be closer.” All too often we never unlearn these; instead, “book learning” gets layered on top long enough for us to pass exams. Then we revert.
Filmmakers at a Harvard graduation provided powerful evidence of this more than 15 years ago, when they asked new graduates why it’s colder in New England in the winter and warmer in the summer. In the 1988 film, “A Private Universe,” each young man and woman explains with perfect confidence that the sun is closer to Earth in the summer and farther away in winter.
Of course, the opposite is true. Earth’s orbit is elliptical, and New Englanders are actually closer to the sun in winter. Earth is tilted away, however, and it is the tilt of its axis that determines the climate.
We can assume that nobody taught those Harvard seniors bad science. Instead, they probably intuited that “fact” when they were young and never unlearned it. Since they were admitted to Harvard, they must have learned enough classroom science to get high grades on tests, but without dislodging or unlearning what they thought they knew from observation. As Lee Shulman, the president of the Carnegie Foundation for the Advancement of Teaching, has noted, “The first influence on learning is not what teachers do pedagogically, but the learning that’s already inside the learner.”
How do teachers help their students unlearn? Cary Academy’s Scott Byington forces students to confront their assumptions (we have more chromosomes than potatoes) because he knows that mere rote learning of scientific facts doesn’t do the trick.
Melanie Krieger, the director of research at Plainview-Old Bethpage J.F.K. High School on New York’s Long Island, believes that hands-on, project-based science helps students unlearn. Her students in grades 9-12 must develop and carry out research projects, usually with the help of real scientists working at nearby labs, hospitals, and technology companies. I watched Samuel John and Omar Ghani catch carpenter ants for their project a couple of years ago: developing ways to kill the ants using only biological controls and natural enemies; in other words, with no pesticides.
Projects like these take months, often including summer vacations, and demand intense work, but the kids don’t mind the work. As Samuel John described it, “Science is hands-on stuff: You learn it, and then you apply it, and the applying part is where the fun comes in.” John’s and Ghani’s carpenter-ant project did not win any awards, but the following year Samuel John scored a clean sweep, winning the Siemens/ Westinghouse, Intel Science Talent Search, and Intel International Science and Engineering Fair competitions. He is now at Rensselaer Polytechnic Institute.
Although Melanie Krieger’s students enter their projects in prestigious science fairs like Intel’s (and sometimes win!), her class is open to all interested students, not merely honors students. She notes that, while about 60 percent of the 100 school districts in her region use the project-based approach to science, only two or three are open to all interested students. “All the other programs have strict entry criteria and quite often seem to look for ways to ‘weed out’ kids,” she says.
If only the elite enjoy the liveliest approaches to science teaching, scientific illiteracy will only increase. That worries Leon Lederman, the Nobel Prize-winning physicist. “Our populations have never been more ignorant of science,” he says, “and yet their lives are being influenced ever more by technological developments: cellphones, implants, and revolutions in molecular biology, genetics, and surgery. There’s so much fake science, junk science, out there, and people have to be able to recognize it.”
Lederman says science teaching can’t be elitist because, as he puts it, “All kids are born scientists. A scientist is someone who asks questions, and kids ask questions. They have those embers of curiosity. You blow on the embers, they get hotter and hotter, until finally they erupt into a flame of passionate interest in the world.”
But too often science class for “regular” students is rote memorization, particularly with today’s emphasis on multiple-choice testing. For example, Maryland’s state department of education was replacing bubble tests with performance-based tests that required students to show how they arrived at their answers. With the advent of the federal No Child Left Behind law’s requirement for testing in grades 3-8 every year, Maryland scrapped its Maryland School Performance Assessment Program and has returned to cheaper, more traditional methods of testing.
High-stakes tests and multiple-choice testing often determine how science is taught, says Leon Lederman, who deplores what he calls a winner-take-all mentality: “Too many kids are having their curiosity stomped out by insensitive teaching in the schools.” Ray Bacchetti, an education veteran who is now at the Carnegie Foundation, shares Lederman’s concern. “I’ve been in too many elementary schools where the reading and math emphasis was sucking the oxygen out of just about everything else,” he says. “Teachers would try to work on bits of science ... but seldom with strong curricular strategies, and hardly ever with useful support from their districts.”
Textbooks are another problem. Jonathan Cole of Columbia University found that the outstanding works of history, including textbooks, were apt to contain more references to Madonna, the singer, than to Watson and Crick and DNA. He notes, “College students who don’t major in science probably conclude that scientific developments and accomplishments sprang from whole cloth, because they’re not covered in the books they read.”
Lederman believes a crisis is upon us. “If we don’t fix our science and math educational system,” he warns, “the nation is really in deep trouble. Our economy has been surviving on immigration, but that’s not going to last, because country after country is getting wise and is keeping its scientists at home.”
But despite superficial textbooks, rote teaching, and a shortage of project-based learning, there is hope for science education. Robert Ballard, the scientist and underwater explorer who discovered the wreckage of the Titanic, is one source of inspiration.
Ballard first realized that all of his graduate students were foreign-born. Where, he wondered, were the young American scientists? Then, spurred by the outpouring of letters (16,000 in two weeks) from children after he found the Titanic, he created the Jason Project (www.jasonproject.org) to allow middle school students to go on “virtual explorations.” Like Leon Lederman, Ballard believes most children are natural scientists. “Any parent can tell you kids are fired up with curiosity,” he says. “The first question they ask is why? Our job is to capture that natural curiosity and turn it into a lifelong passion for learning.”
Because of the Jason Project (now celebrating its 15th anniversary), more than 12 million kids have explored the ocean floor, mapped wetlands, and discovered sunken ships and treasures, thanks to the power of technology. Some of these middle-schoolers have grown up and become scientists in their own right, but that’s not Ballard’s goal. Like Lederman, he wants all American citizens, regardless of their occupations, to be scientifically literate.
Another ray of hope, albeit a faint one, emerged when high school seniors were asked pretty much the same question the Harvard graduates got wrong in 1988. The question was on last year’s National Assessment of Educational Progress science test, and 40 percent got it right. That’s not good enough, but it’s better than Harvard did.
Vol. 24, Issue 24, Pages 40,56