Imagine that you are a student in an advanced high school physics class. The subject of today's lesson is electrostatic forces and fields. You've already learned some of the concepts from lectures and textbooks. But today, your studies are about to enter a whole new dimension--literally.
Your teacher helps you strap on a heavy piece of headgear with glasses that completely blocks your view of the classroom. In your right hand, the teacher places what feels like a billiard ball but what is actually a three-dimensional computer mouse. Another control device fits into your left hand.
At first, you see only darkness. Then, as the controls are adjusted and you become oriented, you find yourself inside a black, three-dimensional box. As you raise your left hand in front of your face, a computer menu appears in the box. The ball in your other hand controls a computer-generated "hand" that you navigate around the box. Use it to point to an item on the menu, and the world of electric forces and fields unfolds.
With your electronic fingertip, you plunk test charges of varying magnitudes into the box. Suspended there, the charges look like tiny, colorful spheres. You watch--and even hear and feel--how they interact with other charges in the box. You see the magnitude of the charges and the direction of the forces they create. Click to another spot on the menu, and your finger traces the vividly colored electric field lines that leap from each charge. Point to a charge, and your finger becomes a meter to help you explore the distribution of electric potential in the black space.
Welcome to MaxwellWorld, one of three virtual reality programs created by researchers at George Mason University, the University of Houston, and the National Aeronautics and Space Administration's Johnson Space Center to enhance the teaching of science concepts.
"A bunch of different groups--the military, medicine, and industry--have used virtual reality for training purposes," says Christopher Dede, lead researcher on ScienceSpace, the project designing the virtual reality programs. "What we were interested in exploring was whether we could use virtual reality for broader things, like education, and whether it could be used with much younger ages." The results so far suggest that the answer to both questions is yes.
Virtual reality technology relies on supercomputers to produce three-dimensional worlds in which viewers become actors rather than mere observers. NASA has used the technology to train technicians to perform tasks in space. And the U.S. Army uses it to simulate unfamiliar terrain for soldiers in training. The soldiers wear virtual reality headgear as they walk on treadmills--an exercise that makes it seem as if they are actually walking in the new landscape.
"NASA had a lot of money--but not anymore--and virtual reality environments look to be cheaper," says R. Bowen Loftin, who heads the agency's part of ScienceSpace. "There's a growing body of literature on virtual reality, and all the papers but one support the effectiveness of the approach."
But while cost-effective for the military and NASA, virtual reality is financially out of reach for most schools. The graphic supercomputers used to power the technology run $250,000 or more. But Dede, who has built a career out of exploring educational uses of cutting-edge technology, predicts that the price tag will rapidly fall as video game manufacturers, attracted by virtual reality's commercial appeal, undertake their own research and development. Many of those companies are already hard at work in their laboratories. "This will be under-the-Christmas-tree technology in a decade," predicts Dede, a professor of education and technology at George Mason University in Fairfax, Virginia.
Dede and his partners believe the new technology is particularly well-suited to teaching science. "We know there are some things that are very difficult to teach," he says, "that instructors complain about in the science curriculum--either because the real world behaves so differently or because it's so contradictory to students' experience that they don't believe it."
He offers Newton's laws of motion as an example. One of those laws holds that an object remains at rest or in motion unless acted upon by another force. Anyone who has rolled a ball on a flat surface knows that it will eventually come to a stop, seemingly on its own. But in reality, the ball slows and stops because of the unseen forces of friction and gravity. "In a lot of physics, you depend fairly heavily on visualization," notes Edward Redish, a University of Maryland physics professor who worked on MaxwellWorld. "Many of my students have trouble understanding what they're seeing when they look at a picture in a book that is supposed to be two-dimensional. And pictures that are supposed to be slices of a three-dimensional view are often misinterpreted by students."
What virtual reality can do--and, indeed, what the ScienceSpace project has done--is create three-dimensional, multisensory worlds that are true to the laws of science. Students using MaxwellWorld can see that electric field lines run in every direction. Giving students seemingly real experiences in those worlds could prevent or dispel misconceptions, the researchers say. It could also attract youngsters to science. "If we can get these worlds gamelike and playful," says Dede, "we can also get some motivation there."
Work on the ScienceSpace project began in 1994 with an initial $1 million grant from the National Science Foundation. The effort is scheduled to run two more years. Besides MaxwellWorld, the research team has created NewtonWorld, which helps students in upper-elementary grades and beyond explore Newton's laws of motion free of the confounding effects of gravity and friction, and PaulingWorld, which simulates mo-lecular structure and chemical bonding. In each of the three "worlds," students not only see phenomena but hear and feel them, as well. In MaxwellWorld, a tone increases in volume in direct proportion to the strength of the electric charges, and cushions fastened to viewers' backs vibrate in a similar manner.
The George Mason research team, working with physicists, chemists, and psychologists, designed the worlds; NASA researchers developed the software. The team then tested it on approximately 150 teachers and students over the course of five experiments. "We're not true believers in virtual reality; we are agnostics," Dede says. "We're listening closely to teachers and students. But what we can say is our data are suggestive that there's power here, and that this is going to take some time to understand."
In one experiment, the researchers compared MaxwellWorld with EM Field, a two-dimensional computer program that teaches many of the same concepts. They chose 14 students who had taken similar one-year physics courses and tested them on concepts both programs address. Then half worked with MaxwellWorld, the other half with EM Field. The researchers found that students in both groups deepened their understanding of electrostatic forces. But the students who used MaxwellWorld were slightly better at defining and sketching phenomena and describing the three-dimensional nature of electric fields and potential. Moreover, the MaxwellWorld students were more excited by the technology--a finding that has emerged in other ScienceSpace studies.
"Immersion in a virtual reality environment," Dede says, "does seem to be stimulating and intriguing for students even after the novelty effects wear off."
Paul Oliver, a 5th grade teacher from Centreville, Virginia, who tested some of the ScienceSpace programs, believes his students "would kill" to work with it. "I talk to them about it all the time," he says, "and their eyes are as big as golf balls."
But not all the findings have been rosy. The researchers discovered, for example, that some students--particularly younger ones and those more familiar with video games--are far better at navigating virtual worlds than others.
Perhaps more troubling is the problem of eyestrain, which some users feel after using the equipment for a half-hour or more. Also the headgear, which weighs about three pounds, can cause sore necks. (Dede predicts that future models will be no heavier than a baseball cap.)
A small percentage of experimental subjects--somewhere between 3 percent to 7 percent--suffer mild motion sickness from the disorienting virtual environment. One percent of users experience such strong bouts of motion sickness that they can't tolerate the virtual world at all.
"If someone is actually susceptible to motion sickness, it doesn't go away in these environments," says Marilyn Salzman, a doctoral student in psychology who is working with Dede. The researchers have found, though, that they can lessen the effects of motion sickness for some by redesigning certain elements of the programs.
As with other educational technology, virtual reality has critics who argue that the technology can never take the place of good teaching. "You have to understand what students' difficulties are in order to use MaxwellWorld," says Redish of the University of Maryland. "If students go in with misconceptions, MaxwellWorld may only confirm them."
And then there is the cost. Enthusiast Paul Oliver, like other teachers, worries that schools will never be able to afford virtual reality equipment.
To address these concerns, Redish plans to experiment with MaxwellWorld on a wide screen. He will project the images for students wearing 3-D glasses and explain the phenomena as he goes along. Students will not be able to manipulate the material as they can in a true virtual environment, but, Redish points out, they will all be on the same instructional page.
For his part, Dede hopes to find ways to open virtual worlds so participating students can interact with one another. In its experiments, NASA has used virtual technology to link astronauts in Germany and in the U.S. for simulta-neous training exercises.
What the researchers hope to have at the end of their five-year project is at least a set of principles to guide the effective design of virtual reality environments for educational purposes. The rest, they concede, will probably be up to the video game manufacturers. "My question," Dede says, "is: Can we find something better than Super Mario III to put in those cartridges?"
The ScienceSpace project maintains a home page on the Internet's World Wide Web at http://www.virtual.gmu.edu.