Evolution Debate Accents Deeper Science Disquiet
On the ocean-like expanse of American science education, it's often the
tempest over teaching the theory of evolution that draws attention. But
beneath the surface pulls a broad and, some would argue, more
troubling, undercurrent: Do teachers of the subject understand science
well enough to enlighten students on evolution or any other
When the National Academy of Sciences published a guide on teaching evolution last month, it was no accident, then, that it also focused on what teachers should know and explain to students about the nature of science.
Understanding that science is one way of knowing about the world, experts and science educators argue, is essential to comprehending scientific theories, or explanations, for how nature works--whether it's the theory of evolution or the theory that the planets revolve around the sun.
Yet, many teachers, whether they're instructing kindergartners or high schoolers, don't have a good grasp of the nature of science, the scientific method, or the idea that a scientific "theory" is not just a guess or hunch, practitioners and observers agree.
The importance of understanding how scientists go about their work becomes especially critical when students or parents who believe in the literal truth of the Bible's account of creation challenge evolution or argue for "equal time" for creationism. If teachers, already shaky in their knowledge of science or evolution, feel intimidated, "that causes the problem to mushroom," said Gerald Skoog, an education professor at Texas Tech University in Lubbock.
"Many teachers feel that 'intelligent design' or creationism should be taught out of fairness, and that, to me, suggests a poor grounding in terms of what science is," said Mr. Skoog, a former president of the National Science Teachers Association. "You don't teach ideas which don't have scientific grounding out of a sense of fairness," he said.
At the same time, Mr. Skoog acknowledged, teachers simply reflect their culture. A 1996 federal report described a survey of American adults that found that 64 percent, or nearly two-thirds, were unable to characterize scientific inquiry in even broad terms. Only 23 percent, or fewer than one in four U.S. adults, understood scientific inquiry well enough to assess whether a study described in a news story constituted a scientific inquiry.
To understand why there is resistance to evolution as an explanation for the diversity of life on Earth, you have to understand the nature of science, said Eugenie C. Scott, the executive director of the National Center for Science Education in El Cerrito, Calif.
"The public and most anti-evolutionists think of science as direct experience and direct observation: 'No one was there; it's not science.' But there's an enormous amount of science that's not done through direct observation," said Ms. Scott, an anthropologist whose nonprofit group strongly supports the inclusion of evolution in the curriculum.
Not the 'Supernatural'
If teachers had a better understanding of what science is, and what its limitations are, many of the conflicts over evolution could simply be avoided, argued Danine Ezell, a science resource teacher for the San Diego schools.
"Scientific knowledge is tentative," she said. "Science is the best answer that we have based upon the best evidence that we have.
"Science should not be dogmatic. ... It's looking at nature rather than at the supernatural," said Ms. Ezell, who served on the panel that wrote the national academy's guide to teaching evolution and the nature of science.
The board of directors of the National Association of Biology Teachers took a similar view last fall when it voted to alter the group's definition of evolution. Instead of its existing description of evolution as "an unsupervised, impersonal, unpredictable, and natural process," the board narrowed it to "an unpredictable and natural process." That change avoided a stance that supporters of the new wording say had encroached on religion.
"The way the definition was stated before was really mixing together theology with science," said Alvin Plantinga, a philosophy professor at the University of Notre Dame, a Roman Catholic institution in South Bend, Ind., and one of two philosophers who suggested the change. "It's not a piece of science to say evolution is unguided or a totally blind process ... that's really theology."
Out of Subject
A spotty understanding of the nature of science is a problem for teachers across grade levels, Ms. Scott said, but it is much more the case for teachers of the elementary and middle grades.
High school science teachers are much more likely--and in some states required--to be specialists in their subjects. Even so, according to U.S. Department of Education data from 1993-94, the latest available, one out of four secondary school teachers of biology neither majored nor minored in it. About three out of 10 chemistry teachers were similarly unqualified, and nearly 60 percent of secondary physics teachers neither majored nor minored in the subject.
Meanwhile, "science phobia" is rampant among elementary teachers, Ms. Scott and others say. "There are elementary teachers who will pick up a picture book on snails, read [to the students] on snails, and consider that they've spent their 45 minutes a week on science."
Colleges and universities bear much of the blame for teachers' attitudes and lack of knowledge about science, many experts say.
"I lay the fault directly at the foot of college professors in science," said Ms. Scott, who used to be one. "The professors are not doing a good job of helping teachers understand what science is, or what evolution is, for that matter."
Ken Ridgway, a Purdue University scientist working to improve undergraduate science education, agreed. "Most research institutions like Purdue ... teach undergraduate courses to make scientists," said Mr. Ridgway, an associate professor in the earth and atmospheric sciences department at the university in West Lafayette, Ind. "But I don't think it really helps the preservice teacher."
Achieving success in those classes often means being good at math and having the kind of memory that can regurgitate facts, he said. "But it doesn't really teach you a whole lot about teaching."
Shoring Up Knowledge
Scientists and teacher-educators at Purdue this academic year have been working together on a pilot study to improve undergraduate courses in earth science, biology, and chemistry.
In addition to attending lectures, some students from large undergraduate science courses, regardless of their intended career paths, are given supplemental small-group sessions or "recitations" in which they go on field trips, among other activities. For instance, in the chemistry-course recitation, Mr. Ridgway said, students are asked before a unit on thermodynamics to draw or map out their understanding of how that concept works. At several points during the unit, students are again asked to draw a "concept map" of their understanding of thermodynamics. That way, he said, instructors can catch misconceptions early.
Such activities as field trips and concept maps are tools that future teachers can also use later with their own students, Mr. Ridgway said.
With one semester of the pilot study concluded, the researchers have found that students in the chemistry course who had been in the recitations and drawn the concept maps did better on the exams than students who hadn't.
For teachers whose undergraduate preparation was lacking, some districts are offering professional development to help shore up their understanding of science. But observers argue there's not nearly enough inservice training on science content compared with how much there is on keeping order in class or using the latest gizmo.
One of the ways the 36,000-student Chesapeake, Va., district responded to a recent parental challenge to the teaching of evolution was to make sure teachers had a review of the nature of science. A panel of about 20 teachers last summer wrote a 10-page addendum to the district's curriculum guide. The addendum, for teachers of grades 6-12, included a definition of science, a discussion of the nature of science, a sample lesson plan on the scientific method, and a glossary of terms. Then, the district's science supervisor visited all 16 secondary campuses--more than once--to make sure everyone understood it.
In Buffalo, N.Y., a five-year, $4.2 million National Science Foundation grant is making possible an effort to enhance the science understanding of all the district's 1,400 K-8 teachers.
Some teachers come into the Team 2000 workshops saying that the last time they took science was in high school, said Cathy Chamberlin, the project administrator of Team 2000.
In the program, a collaboration between the Buffalo schools and the Buffalo Museum of Science, the teachers perform hands-on activities, interact with scientists, and see that they and their students can do "real science," too, Ms. Chamberlin said. "Once they feel it isn't a threatening thing, they're more relaxed and they're more able to soak in the knowledge."
Since the program began, students' scores on district exams have gone up, and principals are upbeat, she said. "Principals are thrilled that science is being taught. For the greatest period of time, teachers tended to stay away from it."