Setting the Record Straight
In a famous 1989 documentary, filmmakers ask newly minted Harvard University graduates a very basic question: Why is it hotter in the summer and colder in the winter?
The students, still wearing their caps and gowns, confidently oblige their interviewers. It's warmer in summer, many of them explain, because the Earth is closer to the sun at that time of year.
Unfortunately, that's the wrong answer.
The correct explanation has more to do with the angle of the sun's rays as they cut through the Earth's atmosphere. Almost everyone learns about the movements of the Earth and the sun in grade school, and surely these graduates, representing the cream of the nation's higher education system, learned those lessons back then, too. Yet, when put on the spot, they clung to misconceptions hatched in their minds at the start of their schooling.
Most people harbor such mistaken, yet remarkably resilient, ideas. Acquired early in life, they are a way of making sense of an unfamiliar world. The problem is that they get in the way of true understanding.
Students who can recite Newton's laws of motion on a test may flounder when given a real-life problem demonstrating the same concepts. If they can't apply a new concept, they don't really know it.
That's why researchers over the past 30 years have put considerable effort into understanding the kinds of ideas that set up roadblocks in the learning process.
Now, some of that work is bearing fruit. Scientists are learning where misunderstandings come from and how to address them.
So far, the bottom line in all the findings is that educators need to be paying much closer attention to what goes on in their students' heads.
"If they're not," says Jose P. Mestre, a physics professor at the University of Massachusetts at Amherst, "they're really teaching at their own peril because students may not be understanding.
"Finding the Sources
In the first half of the century, the Swiss psychologist Jean Piaget was already looking into some of the erroneous ideas that stick in children's heads despite their teachers' best efforts. He observed, for example, that children traveling in a car believe that the moon is following them.
But intensive study into people's misconceptions did not begin until the 1970s, primarily here and in Britain. The early studies, however, often amounted to little more than catalogues of the misunderstandings that are common to different disciplines. The turn toward thinking about possible sources of those ideas and what to do about them has been more recent.
"To give a list of misconceptions, to me, borders on unethical because it's like, 'so what?' " says Ann Kindfield, an education consultant who has studied students' conception of biological processes. "But what we can provide now is information on what are the possible sources of misconceptions."
Along the way, experts grew dissatisfied with the term "misconceptions" itself , fearing that it implies somehow that students are at fault for such mistaken notions. They now use terms such as "alternative theories," "naive understandings," or "primitive conceptions'' to describe those stubborn ideas.
James Minstrell, a researcher for a private consulting firm in Washington state, calls them "facets of understanding." He coined the term after noticing that children's views about physics could be consistent with those of physicists if the details changed in the problems they were given.
"'Misconceptions' has a negative connotation," says Peter W. Hewson, a professor of science education at the University of Wisconsin-Madison. "I operate on the assumption that these ideas that students have, they have for good reasons."
A teacher, quoting Newton's laws of motion, for example, can tell a student that an object in motion will remain in motion unless acted upon by a greater force. But, in the everyday world, everyone has seen that rolling balls eventually come to a stop without any obvious interference.
Similarly, an apple falling from a tree reaches the ground much faster than a leaf fluttering from a branch—gravitational theory notwithstanding.
"Many ideas in physics and biology are counterintuitive to what we learned from the world, and our experiences tend to support them," says Leona Schauble, an associate professor of educational psychology at the University of Wisconsin-Madison.For that reason, most of the work on misconceptions has come in the sciences—genetics, biology, chemistry, and physics in particular.
Need for Future Study
Some experts stress, however, that something akin to misconceptions occurs in many subjects. In the social sciences, for example, the Harvard psychologist Howard Gardner, best known for his theories on "multiple intelligences," suggests that stereotypes may be a form of misconceptions.
"In history and literature, we don't have theories that are wrong," he says. "We have shortcuts that assume that when something happens to you once, it will happen to you again.
"In mathematics, Kurt VanLehn of the University of Pittsburgh and his colleagues have illuminated some basic misunderstandings that persistently dog children's efforts at three-digit subtraction. A common one is a tendency to subtract a smaller digit from a larger digit even when the smaller digit is the one being subtracted from.
Misconceptions are also found in university classes as well as in K-12 education, in A students as well as in B and C students, in teachers as well as their pupils.
"My perception is that we should be pursuing more work in this area across the educational world,'' says John T. Bruer, the president of the James S. McDonnell Foundation, a St. Louis-based philanthropy that supports research in the cognitive sciences.
Indeed, one of the most striking aspects of these stubborn ideas is their ability to coexist in the mind with information that is directly contradictory. As Harvard researcher David Perkins points out in his book Smart Schools, the graduates in the film documentary must also have known that when it's summer in the Northern hemisphere, it's winter in the Southern hemisphere. How could that be true if nearness to the sun brought on the seasons?
Fixing the Problem
Rather than stamp out the misunderstandings in their students' heads, experts say, educators should seek to work with students and help them reconstruct their ideas. One key to doing that is to find ways to make students' thinking more visible in the classroom.
"What one wants to do is get students in discussions so that they may understand their own reasons, understand that there might be alternatives to their own thinking, and to see that ... some ideas might be more powerful than the ones they currently have," says the University of Wisconsin's Hewson. "What teachers need to do is construct a classroom environment where it's safe and open—where it's OK to say what you think.
"Unfortunately, that happens all too seldom, researchers say. Teachers intent on covering all the required material often don't take the time to find out what students think. "Typically, people are in a hurry to get to the right answer, and they tend not to pay attention to the variety of answers that children pose and to how you know which is the right answer," says Schauble of the University of Wisconsin.
Teachers don't have to become cognitive scientists themselves to find out what's on their students' minds. Veteran teachers know intuitively where some of the hitches are in the learning process.
But they don't often share that information. And the research offers some clues on where and how to look for students' confused thinking.One technique for incorporating student thinking into learning, Schauble says, is to ask children to make predictions about scientific phenomena and to discuss their ideas with their classmates. From those discussions, teachers can derive broad categories of predictions.
On a bulletin board, students can post their names under the predictions that make sense to them, then move their names around as activities they do in the classroom lead them to change their minds—or not.
Minstrell, a research scientist for Talaria Inc., a Seattle-based consulting firm, developed a software program 10 years ago that diagnoses students' preconceptions in middle school and high school physics and prescribes classroom activities to help them rethink those ideas. The program, written with a University of Washington psychology professor, Earl Hunt, grew out of Minstrell's experiences teaching the subject at a Seattle-area school in the 1980s. Minstrell would routinely present his students with physics problems at the start of a unit and then elicit their predictions.He began to view the misconceptions as "sort of like hypotheses that students had about the way the world worked," he recalls. "What I had to do as a teacher was to be clever enough to design experiences that would cause students to reflect on and rethink their ideas.
''In one experiment involving 180 high school students using the program, called diagnoser, only 3 percent of the students demonstrated an understanding of some difficult buoyancy and gravity concepts on the preinstruction quiz.
At the end of the semester, though, 61 percent of the students chose appropriate answers to the same kinds of questions. Better yet, they were able to defend their conclusions in writing. On an end-of-the-year final exam given months later, similar percentages of students were still answering such questions correctly.
The remaining students, while not providing the kinds of answers found in physics textbooks, also showed evidence of moving toward deeper understanding.Minstrell is at work on a similar program designed to probe and address students' knowledge in the physics topics covered on statewide tests in Washington.Balancing Balloons
More recently, John Clement, a researcher at UMASS-Amherst, devised an approach known as "bridging." He starts by using student beliefs that are correct and then presenting students with analogous situations to them build bridges to new understandings.
One example: When looking at a book on a table, students tend not to believe that the table is exerting an upward force on the book. Students might agree, however, that a spring exerts a force on a book that is resting on it.
Starting with that idea, Clement asks students whether a book resting in the middle of a long, springy board is experiencing an upward force. To make the concept even clearer, students might be asked to push down first on the spring and then on the springy board. Do they feel resistance in both cases? In the studies that Clement has published in research journals, the proverbial light bulb usually goes on in students' heads at that point.
Ronald K. Thornton, a physicist and science education researcher at Tufts University in Medford, Mass., combines interactive classroom discussions with demonstrations using special microcomputer-based equipment that helps students visualize physics principles that are removed from their own realities.In one example, a heavy cart moving on a frictionless track collides with a smaller, lighter vehicle that is standing still. One of Newton's laws of motion states that, on contact, both vehicles will experience an equal and opposite force. But most students, thinking of Mack trucks ploughing into Volkswagen Beetles, tend to predict that the larger, moving vehicle is doing all the work.
To convince them otherwise, Thornton hooks each vehicle up to a force probe that displays on a large screen the magnitude of the forces acting on each vehicle. "In good situations where the materials are used in ways that we've developed them to be used, we can reach 80 to 90 percent of students who don't know a concept," he says. In comparison, Thornton's research has shown that traditional, lecture-style teaching is effective for teaching those concepts with only 10 percent of students in both high school and introductory university-level physics courses. His methods have proved effective with physics students from 9th grade up.
Better Teacher Training
But sometimes it takes more than a demonstration or experiment to shake up students' preconceptions. New York University researcher Susan Carey describes the case of an elementary school teacher who was trying to convince her students that air has weight.
She rigged up a straw with an empty balloon on each end and balanced it, see-saw fashion, on a fulcrum. She then filled one of the balloons with air and the class watched as the end with the air-filled balloon sank. Her students, however, remained unconvinced. Their explanation? Friction.
"Just because you think you're showing somebody something doesn't mean they make of it what you expect them to make of it," Schauble says.In one famous experiment, for example, children taught that the earth was round immediately thought, "Oh, round like a pancake."But before trying to understand what ideas their students hold, teachers have to examine their own misunderstandings, says Tina A. Grotzer, a research associate at Harvard's graduate school of education.
"If they haven't had the benefit of really good science learning—and most of us haven't—teachers hold the same misconceptions as their kids, and they need to work through those earlier models," she says. Some professors help future teachers do that by taking them step by step through elementary science concepts, teaching them the phases of the moon, for example, just as they would to 2nd and 3rd graders.But most education students probably receive little of that kind of instruction.
Part of the problem: It takes time. At all levels of schooling, teaching in ways that help students permanently reshape the ideas they bring to school takes longer than traditional lecture-style, textbook-dependent lessons.
Just exposing children to all the material demanded by academic standards and testing requirements often leaves less time for guided experimentation and demonstration, many researchers say."Some of the tests that we have don't in any way measure students' thinking," Grotzer says. "If you just tell kids what you want them to know," without bringing about real changes in the way they think, then "10 years from now "they'll be saying the same thing they said before you told them."
The Research section is underwritten by a grant from the Spencer Foundation.
Vol. 19, Issue 13, Pages 26-29