The concept of a round Earth isn’t a simpleone for children to acquire. Their every-
day experience reinforces their deeply held notion thatthe Earth is flat. Told by adults that the Earth is round,they often react by constructing a mental model of theEarth as a pancake, or a terrarium-like structure withpeople living on the flat dirt layer inside, or even a dualmodel with a spherical Earth and a flat Earth coexisting
simultaneously. In effect, childrenattempt to accommodate the newknowledge within the framework oftheir existing conceptual models.Unfortunately, holding tight to thefeatures of those prior modelsinhibits fundamental conceptualchange.
The Round Earth Project is a col-laboration among researchers incomputer science, education, andpsychology. It investigates two alter-native pedagogical strategies forteaching children that the Earth isspherical and the implications ofthat fact. One strategy, which we
term the transformationalist approach, attempts toeffect conceptual change by breaking down the chil-dren’s prior models. In contrast, the selectionist strate-gy attempts to effect learning in an alternative setting(in our case, a small-diameter asteroid), free of preex-isting biases, and to relate that learning back to the tar-get domain—the Earth.
Virtual reality (VR) technologies support both peda-gogical strategies. In the transformationalist approach,VR simulates the launching of a spacecraft from theEarth’s surface and subsequent exploration within afixed-height orbit. In the selectionist approach, VR sim-ulates a small-diameter asteroid. Thus learners maywalk on a body with a curved horizon, see objectsappear from below the horizon, take a long walk around
the entire globe, and come back to where they started.In both environments, distributed VR technologies pro-vide a collaborative learning environment promotingpositive interdependence among pairs of learners.
Initial pilot studies involved bringing children to theVR equipment in the laboratory. However, the actualstudies bring the VR equipment into a local elementaryschool as part of an ongoing research program lookingat the use of VR in conceptual learning for children.
VR and learningResearch in conceptual learning using VR is a rela-
tively young field, but growing rapidly. In a recent reportby the Institute for Defense Analysis, Christine Young-blut comprehensively surveyed work over the past fewyears in the area, citing approximately 50 VR-basedlearning applications and 35 studies that include desk-top but exclude text-based virtual environments.1
Currently there exist very few VR-based learning envi-ronments designed for young children and only twomultiuser virtual educational worlds: Virtual Physics atthe University of Lancaster2 and NICE (Narrative,Immersive, Constructionist/Collaborative Environ-ments) at the University of Illinois at Chicago.3 Othereducational VR worlds such as the ScienceSpace4 worldsare being extended to support multiple users. Collabo-ration encourages conversation, and conversationserves learning by presenting each learner with a slight-ly different view of the subject matter. Individuals mustenrich their own representations in order to assimilatetheir partner’s discourse. Conversation also improvesevaluation. Rather than thinking aloud, the participantstalk to each other.
NICE, an exploratory learning environment for chil-dren between the ages of 6 and 10, explicitly attemptedto blend several learning and pedagogical themes with-in a single application. These themes—constructionism,exploratory learning, collaboration, and the primacy ofnarrative—reflect several of the most important educa-
Andrew Johnson, Thomas Moher, Stellan Ohlsson,and Mark GillinghamUniversity of Illinois at Chicago
The Round EarthProject—Collaborative VRfor ConceptualLearning
tional reform themes of the past three decades. TheNICE garden was originally designed as an environmentfor young children to learn about the effects of sunlightand rainfall on plants, the “spontaneous” growth ofweeds, the ability to recycle dead vegetation, and simi-lar simple biological concepts that are part of a garden’slife cycle. NICE supported real-time distributed collab-oration with voice communication enabled by a real-time audio connection.
While NICE succeeded as an engaging social spaceand as a driver for collaborative VR, the cooperativelearning was unstructured and undirected. As its suc-cessor, the Round Earth Project builds on the experi-ence gained from NICE and seeks to remedy thesedeficiencies.
We focus on learning problems that meet four criteria:
1. The learning goal must be important. That is, it mustbe identified as a component of adult scientific (orother) literacy as reflected in national learninggoals, standards, or benchmarks, such as Curricu-lum and Evaluation Standards for School Mathe-matics by the National Council of Teachers ofMathematics or Science for all Americans: A Project2061 Report on Literary Goals in Science, Mathe-matics, and Technology by the American Associa-tion for the Advancement of Science.
2. The learning goal must be hard. That is, it must bereflected in the literature of researchers and/orpractitioners as difficult to effect and resistant toconventional pedagogical strategies.
3. The learning goal must be plausibly enhanced bythe introduction of immersive VR technologies.
4. Finally, VR-based learning environments must beinformed by contemporary research in the learningsciences and educational practice.
Young children believe the Earth is flat. More pre-cisely, their mental model of the world separates sky andearth into two parallel layers, one above the other; thetwo directions up and down are absolute. Empiricalstudies have demonstrated that telling young childrenthat the Earth is round doesn’t cause them to replacetheir intuitive model with a spherical conception of theEarth. Instead, children assimilate the new informationinto their prior knowledge and conclude that the earthis flat and circular.5-7 Conceptual models of the earth asa pancake shape, as a partially compressed ball, andeven as a “terrarium” (spherical but hollow, with a holein the top for sunlight and half filled with dirt uponwhich people reside) are common in children of this agegroup (5 to 10 years old).
Children’s intuitive model of the Earth is consistentwith, and strongly supported by, everyday experience.Discourse has little impact, not only because words like“round” are ambiguous but also because talk about theEarth is abstract and cannot compete with the vividnessof looking upwards when looking at the sky or seeingthe ocean with its straight horizon. Pictures have littleimpact because they require a complex mappingbetween experience and the 2D plane. To understand apicture of a person on a spherical body, the viewer must
project himself or herself into the picture—a cognitivecapability beyond very young children. The same is trueof a 3D representation such as a globe. However, in VRthe children can be immersed in the experience if walk-ing on the spherical surface of a small planetary bodysuch as an asteroid.
Teaching young children that the Earth is sphericalmakes a good match with our four criteria:
1. In AAAS Project 2061: Benchmarks for Science Lit-eracy, fifth-grade graduates should know “things onor near the Earth are pulled toward it by the Earth’sgravity” and “the Earth is approximately spherical inshape.” Eighth-grade graduates should know“everything on or anywhere near the Earth is pulledtoward the Earth’s center by gravitational force.”The spherical Earth is also reflected in local stan-dards as part of the State of Illinois Learning Goal13 (“Understand the fundamental concepts, princi-ples, and interconnections of the life, physical, andearth/space sciences”) and is a regular componentof the local district’s science curriculum for first- andsecond-grade students.
2. The existing literature by Vosniadou, Brewer, andNussbaum discuss the difficulty of this learningproblem.5-7
3. Immersive VR is well suited to giving a person thesense of walking on a spherical object with smalldiameter, seeing objects appear from below thehorizon, and returning to the starting point after cir-cumnavigating the sphere.
4. The environments designed in this project empha-size role differentiation with positive interdepen-dence and collaborative learning.8
Deep learningUnderneath the extensive systems of domain-specif-
ic knowledge that a person brings to bear on problemsand situations, there exist organizing concepts—fun-damental ideas—that influence how a person concep-tualizes both direct experience and discourse withinthat domain. Such deep ideas form the axiomatic coreof entire systems of knowledge.9,10 When experience ordiscourse attempts to communicate a deep idea bothdifferent from and more fundamental than the learn-er’s existing ideas, a paradox occurs. Although the intentis to replace the learner’s existing ideas, those existingideas are the learner’s only tools by which to acquire thenew idea.
If this learning paradox is real, then how does anyoneever learn anything new? Our approach to this questiondistinguishes between transformationalist and selec-tionist explanations of cognitive change. The transfor-mationalist account assumes that operations on priorknowledge create new knowledge. Prior knowledgeserves as raw material, and the new knowledge resultsfrom generalization, specialization, or some other cog-nitive operator applied to the raw material.
The selectionist account of cognitive change assumesthat a new understanding of a domain or phenomenonbegins by establishing an alternative cognitive startingpoint—an idea or concept is established outside the
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learner’s existing system of domain knowledge. Initial-ly such an alternative representation might be rudi-mentary and hence dominated by the priorwell-established representation. However, over time allavailable representations compete and a representationthat proves useful in dealing with certain types of situ-ations or problems gradually gains strength and mayeven displace the previous representation.
The selectionist framework suggests a particularinstructional strategy for supporting deep conceptuallearning—fundamental ideas that contrast with thelearner’s current ideas need to be established on theirown terms before they are brought into contact with thelearner’s prior ideas. VR, we believe, provides a power-ful tool in helping to create such alternative cognitivestarting points. We can also use VR to juxtapose andswitch between multiple interlinked representations ofthe same experience. Our natural tendency in assimi-lating new information is that each facet of reality tendsto be conceptualized in only one way, within a singleperspective. Impasses on simple problems occur becausethe thinker assimilates or subsumes the problem undera prior conceptualization that doesn’t support the solu-tion. Switching representations is difficult, but deeplearning may require precisely such shifts between alter-native representations.
While we believe it’s crucial to construct these alter-native mental representations, our overall strategyrequires a second step. The alternative representationsmust be brought into contact with the learner’s priorknowledge of the domain and absorb or subsume it.Unless learners bring their new experience on the aster-oid into contact with the everyday experience of walk-ing on a seemingly flat Earth, they don’t reach thelearning objective. The point is not just to know what itwould be like to walk on a spherical planetary body, butto understand that the Earth is such a body. We call thissecond step bridging activities.
Asteroid world and Earth worldFor the selectionist approach the children begin at an
alternative cognitive starting point: a small asteroid.
Here they can learn about walking around a sphericalbody different from the Earth. For the transformation-alist approach the children begin on the Earth andattempt to transform their current flat Earth model intoa spherical Earth model.
We wanted the children to see both the spherical rep-resentation of the planetary body as well as the flat viewfrom the surface and integrate these two views. Becauseof this we made the world collaborative, with one childexperiencing the world’s surface and the other seeingthe first child’s avatar on the spherical world. We gavethe kids a task to perform so that the child on the sur-face needed to move around the spherical body. Thisway one of the participants would often be upside downon the sphere but right side up on the surface. We want-ed the collaborative task to foster positive interdepen-dence, where neither child could perform the taskalone; they had to cooperate and communicate witheach other. Through this communication the childrenwould need to reconcile their different views. Choosingsimple controls meant little training time was involved,and the children could concentrate on the experience.We wanted to keep them engaged, giving them a longenough experience to grasp the concept but not so longthat they became fatigued.
In both worlds the children must find 10 objects scat-tered around the planetary body. The two children playthe roles of astronaut and mission control. The astro-naut moves around the planetary body collecting eachof the parts, guided by the other child. Mission controlsees a spherical view of the planetary body, as if froman orbiting satellite, and can see the location of each ofthe 10 objects. Each child performs both roles duringthe experience to see both views. We expect that thechildren will successfully collect most or all of the objectsin the allotted time. Even if they don’t collect them all,they’re told that they succeeded in their mission.
In the asteroid world, the two children find themselvesmarooned on the surface of a small asteroid. They needto retrieve 10 fuel cells from the surface and bring themback to the ship. The astronaut starts out in the airlock ofthe marooned spaceship and has 10 minutes to explore
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1 In the asteroid world, the astronaut explores the surface, collecting fuel cells as guided by mission control. Theleft image shows what the astronaut sees on the asteroid’s surface. The right image shows the mission control viewfor the asteroid world, including the astronaut’s avatar.
the surface in search of the fuel cells. The child can carryup to four cells, then must return to the ship to drop themoff. Mission control sees the astronaut as a person in aspacesuit walking on the surface of the asteroid.
After 10 minutes, the astronaut automatically tele-ports back to the ship. The children then switch roles.When both have had their time on the surface, they’retold that they successfully completed their mission. Theyboth stand in front of the ImmersaDesk to see theirspaceship lift off from the surface of the asteroid andbegin the journey home. See Figure 1.
In the Earth world, the two children must retrieve 10parts from a broken satellite scattered in orbit aroundthe Earth and bring them back for reassembly. The astro-naut sits in the command chair of a spaceship on alaunching pad surrounded by skyscrapers in downtownChicago. Since our students live in Chicago, this givesthem a familiar starting point on a very flat-lookingEarth. As the engines roar, the astronaut is launchedinto space. The astronaut sees the buildings, then thecity, then the Earth fall away as he or she rises into orbitto see an Earth with a curved horizon. Once in orbit theastronaut maneuvers the ship close to the satellite partsto retrieve them. Mission control sees the astronaut’spointy space capsule flying over the Earth’s surface.
After 10 minutes the autopilot engages, maneuversthe ship back over the city of Chicago, and lands the shipback on the launch pad. The children then switch roles.When both have had their time in orbit, they’re told thatthey successfully completed their mission. They bothstand in front of the ImmersaDesk to see the recon-structed satellite. See Figure 2.
Pilot studiesTo date, we’ve conducted three pilot studies leading
up to the first formal study. The first pilot study consist-ed of four pairs of children, looking primarily at inter-face and usability issues in the two worlds. The secondpilot study consisted of eight pairs of children, concen-trating on learning in the two worlds, the effectivenessof the bridging activities, and the ability of the pre- and
post-testing to reflect change in the children’s models.These led to changes in our procedures. A third pilotstudy of five pairs of children in the asteroid world eval-uated our modified design. At this point we felt preparedto undertake the first actual study, which consisted of14 pairs of children.
For the pilot studies, the astronaut stood in a standard10-foot Cave Automatic Virtual Environment (CAVE)with three walls and one floor. The astronaut wore a pairof stereo liquid crystal display (LCD) shutter glasses thatalso contained a position sensor for the Flock of Birdstracker and carried the standard CAVE wand—a six-degrees-of-freedom mouse with three buttons and anisometric thumb-controlled joystick. The astronaut’sspeech was picked up via an ambient microphonemounted on the top of the CAVE’s front wall. Audio fromthe application and from mission control were mixedand sent through the CAVE’s speakers. A low-light colorcharge-coupled device (CCD) camera mounted outsidethe entrance to the CAVE sent the image of the astro-naut and the front CAVE screen into the computer forthe ImmersaDesk and into a video cassette recorder(VCR) for recording.
The child acting as mission control stood at an Imm-ersaDesk. Mission control also wore a pair of LCD shut-ter glasses, but no head tracker. We did this so that the 3Dimage of the spherical planet would always remain com-pletely on the screen, no matter how active the childbecame. The joystick served to spin the world, whichcould be turned completely around horizontally withlimited tilt. This let mission control keep the astronautin view at all times, but left the astronaut positioned rightside up in the northern hemisphere, sideways near theequator and upside down in the southern hemisphere.
The camera image from the CAVE was sent into theImmersaDesk and placed on the screen. A head-wornmicrophone picked up mission control’s speech. Audiofrom the application and from the astronaut were mixedand sent through the ImmersaDesk’s two speakers. Alow-light color CCD camera mounted behind missioncontrol sent the image of the child to the VCR for record-
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2 In the Earth world, the astronaut launches from Chicago up into orbit in the cockpit of a spaceship. The astro-naut flies around the Earth collecting parts of a broken satellite, guided by mission control. The left image showswhat the astronaut sees in orbit around the Earth. The right image shows the mission control view for the Earthworld, including the astronaut’s spaceship.
ing. Audio from both the CAVE and ImmersaDeskmicrophones also went to the VCR.
Two adult guides helped the children at the CAVE andImmersaDesk. Initially, the guides simply helped withthe equipment and the initial setup of the task, thoughtheir role became larger as the pilot studies continued.We also modified the bridging activities as the pilot stud-ies progressed. We describe these changes and otherissues the pilot studies raised in the next section.
The children for the pilot studies came from a smallurban Chicago public school with which one of the teammembers had a previous relationship. This element oftrust was very important, as we would be moving thechildren from the school to our lab for the VR experi-ence. The third-grade students at this school scored sig-nificantly below the state and district averages inreading and math, and below the state average in writ-ing. The first pilot study included the children of theteachers and administrators at the school, allowing us tofamiliarize their parents with our procedures. The sec-ond and third pilot studies included summer school stu-dents who did not pass the Iowa Test of Basic SkillsGrade 3 exam. This group seemed like good candidatesfor an alternative learning experience.
Pilot study 1The first pilot study with four pairs of children showed
us several things about the usability of both the aster-oid world and the Earth world. As with the NICE stud-ies, the LCD shutter glasses were too big for smallchildren. The only satisfactory solution we have foundis to tie the glasses on. Initially the asteroid world astro-naut would reach down to physically pick up the fuelcell, while the Earth world astronaut would only haveto pilot his spaceship close enough to the satellite partbefore it was grabbed automatically. The Earth worldchildren had a much easier time than those on the aster-oid world, so we replaced the realistic asteroid worldinterface with automatic grabbing when the astronautgot close enough to the cell. This let the astronaut kidsconcentrate on the important task of moving about theasteroid rather than on the unimportant skill of pickingup fuel cells.
We also simplified the navigation for the astronautchildren in both worlds. From using the analog joystickto move about the asteroid, they went to using the threebuttons to perform turn left, move forward, turn right—easier for small hands to control. We also enlarged therepresentations of the astronaut in the mission controlview to eight times their actual size to make the directionthe astronaut was facing more obvious. Once we madethese changes, the children used the VR technology veryeffectively, and the application remained virtuallyunchanged for the rest of the studies.
Pilot study 2A great deal of component knowledge is subsumed
under the rubric of “knowing that the Earth is round.”We prepared a 16-item questionnaire adapted from pub-lished questions used in earlier studies of children’smodels of Earth5-7 designed to probe for understandingof the following four concepts:
1. The Earth is (roughly) spherical in shape.2. There is no absolute up or down associated with a
particular portion of the Earth.3. The Earth’s surface is continuous and can be
circumnavigated.4. The horizon is a curved edge that may partially or
totally occlude objects on the other side (or inspace).
We soon supplemented these with a 3D sculpting com-ponent using PlayDoh to get a better idea of the child’smodel(s).
The second pilot study involved four sets of two chil-dren in each of the worlds. We conducted individual oralpre-test interviews based on the questionnaire lasting15 to 20 minutes at the school a day or two prior to theirVR experience. We audiotaped these interviews for fur-ther review later.
The children were brought in pairs to our universitycampus, given a cover story describing the Earth worldor asteroid world scenario, and briefly trained by an adultguide in using the VR apparatus. The children spent 10minutes on each task twice, one child as mission controlfor 10 minutes, then astronaut for 10, then mission con-trol for 10, then astronaut for 10. The guides only inter-fered when absolutely necessary, trying to keep the senseof immersion as strong as possible. The children becamevery engaged in the activity, and their sense of presenceseemed high. Several said that they initially felt theywould fall off the world if they walked over the nearbyhorizon, but once they walked over that horizon, theybecame comfortable moving over the surface.
The two distinct interfaces let us employ a tightly cou-pled jigsaw collaboration scheme, alternating each childbetween the two positively interdependent roles ofastronaut and mission control. Most of the childrenactively talked to each other. Unfortunately, the chil-dren seemed almost too engaged in the task, focusingon the goal of collecting the fuel cells or satellite partsand only conversing on that specific topic. The childrentreated the experience as a big, enjoyable video gamethat they wanted to win.
We had thought that the mission control child wouldcomment about the astronaut child being upside downand that the two children would need to integrate mis-sion control’s directions of “go up” and “go down” withthe astronaut’s directions of “go left” and “go right.” Thekids didn’t talk about the other child being upside downand didn’t use any of the available landmarks to aid innavigation. Most mission controllers eventually adopt-ed a strategy of telling the astronaut to remain in placeand turn in either direction until told to stop, then moveforward. The mission control children rarely looked atthe live video image of the astronaut in the CAVE.Instead they concentrated almost exclusively on thecomputer-generated image of the avatar moving aroundthe sphere. The children focused intently on their goalof collecting the 10 objects, and the computer-generat-ed spherical view helped them achieve that goal, whilethe live view did not.
When the two children completed the task, webrought them together in front of the ImmersaDesk for
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a bridging activity. An adult interviewer led themthrough a brief recounting of their experience using themission controller view. Here we found that words suchas horizon weren’t in the children’s vocabularies, mak-ing the bridging activities more difficult than expected.We reviewed and reinforced each of the four identifiedknowledge components in the context of the asteroid.In each case, we told the students that the same factsapplied to the Earth as well, citing similarities and dif-ferences between the two celestial bodies. Immediate-ly following the bridging activity, we brought thechildren to a different room and interviewed them sep-arately using the same questionnaire. Following com-pletion of the assessment, they returned to their school.
For each subject, we reviewed the audiotapes andwritten documents for evidence of learning in each ofthe four component knowledge areas. The results weredisheartening. It became apparent from these questionsthat limited learning was reflected under either treat-ment. Among the kids who began with highly immaturemodels of the Earth’s shape (typically pancake shapes),all continued to hold to their naive models in the post-test interviews. The remaining children had indicateda belief in the sphericality of Earth in the pre-tests, butall fell short on one or more of the remaining knowledgecomponents. Among these we found limited improve-ment in the relativity of up and down questions, and inthe circumnavigability questions. Still, the robust out-come we had hoped for was obviously missing.
We stopped the second pilot study and considered thefactors that may have led to our limited success. Weidentified numerous potential sources: the design of theapplication interfaces, novelty effects, learning andattention deficit disorders among our subject pool, socialand communications difficulties among subject pairs,and more. We focused on what we believed were thetwo most important issues: over-engagement in the taskat the expense of learning, and the failure to bridgelearning about the asteroid to the subjects’ mental mod-els of Earth. We made some significant adjustments toour procedures, focusing for the time being exclusivelyon the asteroid world. Since the children seemed quiteable to use the VR hardware and complete the task, weneeded some way for them to focus less on the task andmore on the concepts we wanted them to learn.
Pilot study 3For the third pilot study with five pairs of children we
modified our approach in several ways. Instead of ashort training time with the guides focusing exclusive-ly on the VR hardware, we now also used this initial timeto point out features of the landscape. The guides gaveeach child an individual five-minute introduction to theastronaut view and a similar introduction to the missioncontrol view, then introduced the collaborative task.The guide showed that if you kept going in the samedirection you would return to where you started andthat objects appeared top-first over the horizon.
Since the introductory time was increased, the chil-dren spent only 10 minutes in each role, rather than twosets of 10 as in the previous study. While walking thechildren between the CAVE and the ImmersaDesk, the
guides reinforced the conceptsbrought up during the training ses-sion. The guides also tried to directthe attention of mission control tothe video window when appropri-ate “right side up in the video” and“upside down on the sphere” situa-tions appeared.
Most importantly, the bridgingactivities changed from a groupdebriefing in front of the Immer-saDesk to individual guided inquiryusing a physical globe of the Earthand a Styrofoam model of the aster-oid. This focused on reminding thesubjects of what they had experienced, how their expe-riences demonstrated the target knowledge compo-nents, and how that same knowledge applied to theEarth. While the ImmersaDesk allowed mission controlto see the astronaut moving over the surface of thesphere, the physical models allowed more direct manip-ulation and interaction between the instructor and thestudent with the model. The instructor could now posi-tion a small astronaut figure at any point on the sphereand manipulate the sphere’s orientation.
We focused on a detailed analysis of individual sub-jects’ protocols. This analysis was complicated by thefact that few instances of complete, fundamentalchanges in conceptual models occurred among subjects.Instead, we saw some subjects holding strongly to theirinitial models, some who appeared to demonstrate tem-porary effective learning during the experiment thatwasn’t reflected the next day, and some who appearedto reflect persistent learning of some, but rarely all, ofthe target knowledge components.
One obvious outcome of the study was the sensitivi-ty of the subjects’ responses depending on the dimen-sionality of the media. The children showed littleconsistency between their 2D and 3D models, oftenappearing to maintain simultaneous separate-but-equalrepresentations. Children who demonstrated effectivelearning when asked to interact with 3D physical mod-els would often revert to flat Earth models when askedto reason on the basis of 2D drawings.
Results of the three pilot studiesSimulator sickness didn’t pose a significant problem
during the pilot studies. In all of the studies, one childreported dizziness during the study, and that childrefused to leave the CAVE. Another child expressed con-cern over sickness prior to the experience, but reportedno difficulties during the experiment.
These three pilot studies with 34 children showed usthat the children could use the VR equipment effective-ly. They were strongly engaged by the nominal tasks,sometimes to the detriment of the target learning, treat-ing the experience like a video game to win rather thana possible source of learning. The children actively com-municated with each other, though again on very task-specific topics. We were encouraged to see clearinstances of learning related to specific knowledge com-ponents of the target concept. For those subjects who
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The children showed little
consistency between their
2D and 3D models, often
appearing to maintain
separate-but-equal
representations.
appeared to undergo conceptual change, we believe thatthe VR experience effectively helped them establish analternative cognitive starting point, as required by theselectionist learning model. These subjects found theasteroid a plausible reality and could use their experi-ence to subsequently reason about how things might beon Earth.
But accepting the VR asteroid as plausible wasn’tenough. Some subjects in the pilot studies who appearedto find the asteroid believable didn’t successfully bridgetheir knowledge to the target domain. For subjects inpilot study 2, we believe that the fault lay in the abrupt-ness of the intended bridging activity. Simply tellingthem that their new knowledge applied to Earth gavethem no tools with which to bridge between two appar-ently dissimilar representations. The pilot study 3 sub-jects who succeeded in changing their concept of Earthdid so, we believe, because the revised bridging proce-dures afforded them a chain of representations fromsource to target domain, with each new representationsufficiently similar to its predecessor for them to accept.
In spite of substantial cooperation by the school andthe children, the difficulties in obtaining parental per-missions, unanticipated absences, scheduling pullouts,and especially arranging transportation (liability con-cerns requiring us to employ unreliable and expensivetaxi services) combined to make logistic supportextremely time-consuming and expensive. Moreover,the process of running two pairs of children through theexperiment typically required six adults for most of aworking day.
You can find more details on the pilot studies else-where.11,12
Formal studyBecause of the constraints in doing the experiments
in the lab, we decided to conduct the actual studiesinside the elementary school itself. When we were readyfor the actual studies, the elementary school from thepilot studies was in the process of changing principals,
so we had to look elsewhere.Because another of the team mem-bers had a long-standing relation-ship with an elementary school inhis district, we again took advantageof a preexisting atmosphere of trustas the basis for working in closecooperation with the teachers andadministration.
Before going into the school, weinvited the principal and teachersfrom various grades to the lab. Wewanted to show them the VR equip-ment, explain the current study andour long-term goals, and discusshow we could work together in theschool.
This elementary school has aracially and economically diversestudent body (29 percent African-American, 35 percent total minori-ty enrollment) and faculty (28
percent minority), and offers diversity of subject mas-tery, as reflected by the Illinois Goal Assessment Pro-gram and Stanford-9 achievement tests administered atthe school. While performing moderately above aver-age as a school, it has significant representation in allperformance quartiles. The school is also roughly aver-age with respect to technology infusion, with about onecomputer for every five children, distributed both inclassrooms and computer lab settings, and an orienta-tion more toward computer literacy and technology edu-cation rather than conceptual learning.
We brought an ImmersaDesk and a stereo-capablemonitor into a classroom in the school for two weeks,and conducted studies on the selectionist-based asteroidworld. The ImmersaDesk was used for the astronautview, giving the user a wide field of view on the surface,while the stereo monitor was used for mission control.The overall setup in the room appears in Figure 3 andthe individual stations in Figure 4.
Since the mission control children in the pilot studiesrarely used the live video feed from the astronaut’s view,we removed that for this study. We again set up videocameras to monitor both children, but used that footageonly for our analysis. We also modified the pre-test andpost-test questions. The pretest now consisted of 18questions spread over five topic areas: the sphericalityand support of the Earth, the relativity of up and down,circumnavigation, occlusion, and egocentric versus exo-centric perspectives. These questions were asked ver-bally, with 2D paper drawings, and using 3D PlayDohmodels to minimize representational bias.
This school had 84 second graders in four classrooms.Since the students would be pulled out of class duringthe regular school day, we needed parental and teacherpermission. Of the parental permission slips distributedto all the second-grade students two weeks ahead oftime, 76 were returned. All of these children took the20-minute pre-test, which took two days for all of them.We developed a simple scoring system and divided thechildren into three groups: the high group answered 14
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3 Photographof the Immersa-Desk and astereo monitordeployed in aclassroom at theelementaryschool. Weplaced theequipment backto back so eachchild could notsee what theother saw.
or more correctly, the intermediate group answered 11to 13 correctly, and the low group answered 10 or fewercorrectly.
We chose the 29 children in the low group for the VRexperience. From our previous experiments with thethird-grade children at the pilot study school, we expect-ed to have a larger subject population. Because we onlyhad 14 pairs of children, we had them all experience theselectionist-based asteroid world. One week later ran-domly chosen pairs of these children came to the class-room, received their 10-minute guided tour of theworlds, received their mission, and then went throughthe 30-minute VR experience and the 10-minute bridg-ing activities. The VR experience and the bridging activ-ities were essentially the same as those in the third pilotstudy. On the next day they took the post-test.
During the experiment one child reported being dizzyat mission control, but wanted to continue. Several ofthe children reported being scared when they firststepped onto the asteroid in front of the ImmersaDesk,and one of the children was unable to continue.
The 22 children in the intermediate group becamethe quasi-control group. These children took the post-test without having the intervening VR experience. Inthe interest of fairness, following the post-tests the chil-dren in the intermediate and high groups had a chanceto experience the VR worlds. It took us four days to givethe experience to the treatment group and then an addi-tional three days for all of the other children. The lastday of the deployment coincided with the holiday singat the school, where we demonstrated the VR equip-ment and worlds to the children’s parents.
The performance of the treatment group increasedfrom a mean of 7.3 correct answers on the pre-test to12.9 correct answers on the post-test; the difference wassignicant (p < .05). Because the pre-test and post-testcontained identical questions, we were concerned thatpractice with the test itself might affect performance.The proper way to evaluate this concern would be toapply the same pre-test and post-test to a control sam-ple drawn from the same population, in our case stu-dents in the low group. We couldn’t do this because we
applied the intervention to all of the students in the lowgroup—both because we didn’t want to withhold whatwe believed would be a valuable learning experience,and because dividing that relatively small sample in twowould have made pre/post significance testing difficult.
In order to estimate the effect of test taking, weemployed the quasi-control group. The performance ofthis group increased from a mean of 12.2 correct ques-tions to 14.0 questions between pre-testing and post-testing. This difference was also significant (p < .05).While a formal comparison is impossible given the orig-inal differences between the two groups, the differencein the magnitude of the change between the two groupsgives at least qualitative evidence that the interventionraised the lower group to roughly comparable perfor-mance with the intermediate group.
Four months later we returned to the school and con-ducted a delayed post-test with the original treatmentgroup. The performance of the treatment groupdecreased slightly to 11.4 correct answers. Because weprovided the treatment to the quasi-control group afterthey completed the post-test, they weren’t candidatesfor delayed post-testing. Decreased levels of perfor-mance on delayed post-tests are the norm; what wasimportant was that the learning effect had persisted.The difference between the pre-test and delayed post-test was still significant (p < .01), while the post-testand the delayed post-test didn’t differ significantly fromeach other (p > .05).
Compared to the pilot studies, this study in the class-room went much faster and required fewer personnel.Our experience with taking VR hardware to conferencesmade the deployment to the school quite straightfor-ward. The children seemed very excited by the experi-ence. As word spread through the school, many childrenand teachers from other grades came by to see what wasgoing on. A group of fourth graders lined up outside theclassroom door at the end of one school day and, afterassuring us that their parents knew they were stayinglate after school, stayed for two hours. Eventually theybrought their teacher down and demonstrated the VRequipment and worlds to him. While we initially thought
IEEE Computer Graphics and Applications 67
4 Two children collaborating on the asteroid. The left photograph shows the astronaut at the ImmersaDesk aboutto leave the spaceship to search for fuel cells, while the right photograph shows mission control preparing to guidethe astronaut on his quest.
that the kids’ familiarity with video games would makethem jaded, our setup was favorably compared to vari-ous video game systems.
There was great interest among the kids and theteachers and principal in having us return to the schoolfor future work, but winning hearts is not the same aswinning minds. Adding more activity to an alreadycrowded curriculum will garner long-term support onlywhen we can convince the teachers that it will advancetheir goals of ensuring student success.
Conclusions and future workWe’re continuing to analyze the results from this
study, looking in more detail at individual children andperformance on particular knowledge components. Weare going to run several more experiments using theround Earth worlds. The first will compare the asteroidworld to the Earth world. The second will investigatethe relative effect of the VR experience and the bridg-ing activities on learning. While we designed the twoworlds to be collaborative, we also want to investigateletting a single user switch between the two represen-tations at the ImmersaDesk or seeing both of themsimultaneously. We also wish to further investigate thereasons for the differing success rates in the final pilotstudy versus the first actual study. Given the differencesin the VR experience itself, the questionaire, and thelocation of the study, it’s difficult to draw any meaning-ful conclusions at this time.
The Round Earth Project is part of a larger researcheffort to help prepare schools for the advent of advancedvisualization technologies such as VR. We’re trying toidentify appropriate roles for those technologies with-in the context of learning and instructional theories,constructing and evaluating learning environments, andultimately producing design support and working learn-er-centered applications for use in real elementaryschool settings.
Our focus is an investigation into the design, coordi-nation, and effectiveness of multiple advanced visualrepresentations of scientific phenomena in children’slearning. You only have to open a science textbook tosee the central role that multiple representation plays,but in order to benefit from multiple representations,the learner must be able to map between them. Manypossible relationships exist between representationsincluding exocentric versus endocentric, spatial dis-placement, scale, part-whole, and degrees of realism.Each type of relationship poses a different challenge forthe learner to create the appropriate mapping. Underwhat conditions the benefit of these multiple represen-tations offsets their increased cognitive load remains anopen question. We believe that explicitly supporting thelearner’s task of constructing these mappings, eitherthrough discourse or explicitly embedding this mappingwithin the visualizations, will improve their effective-ness. We plan to develop both discourse-based andembedded support and compare their effectiveness ina variety of representational relationships. As part ofthis continuing work, we returned to Abraham LincolnElementary School and installed an ImmersaDesk,which will remain on site for the next two years. ■
AcknowledgmentsThere are many people involved in the Round Earth
project. In addition to the authors, the Round Earthteam includes Joe Alexander, Tom DeFanti, Josh Hem-merich, Jyoti Jain, Mark Orr, Carlos Orrego, Maria Rous-sou, and Mike Trolio. We also gratefully acknowledgethe assistance of Julieta Aguilera, Josephine Anstey, JimCostigan, Greg Dawe, Tom Frisch, Steve Jones, JasonLeigh, Dave Pape, Sam Throngrong, and Fang Wang.
We wish to thank Shirley Woodard, Program Direc-tor, and Anthony Biegler, principal of South Loop Ele-mentary School, and Carol Dudzik, principal ofAbraham Lincoln Elementary School, for their effortsin encouraging and coordinating student participationin the studies.
This research was supported by funding from theNational Science Foundation, award EIA 9720351 -Deep Learning and Visualization Technologies.
The CAVE and ImmersaDesk are trademarks of theBoard of Trustees of the University of Illinois.
References1. C. Youngblut, Educational Uses of Virtual Reality Technolo-
gy, Tech. Report IDA Document D-2128, Institute forDefense Analyses, Alexandria, Va., 1998.
2. P. Brna and R. Aspin, “Collaboration in a Virtual World:Support for Conceptual Learning,” Proc. of 1st Int’l Conf.on Virtual Reality in Education and Training, Loughbor-ough, UK, June 1997.
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Virtual Reality
68 November/December 1999
Andrew Johnson is an assistantprofessor in the Electrical Engineer-ing and Computer Science Depart-ment at the University of Illinois atChicago. His current research focuseson tele-immersive virtual environ-ments, in particular their application
in education. He received his BS in computer engineeringfrom the University of Michigan, and his MS and PhD incomputer science from Wayne State University.
Thomas Moher is an associateprofessor in the Electrical Engineer-ing and Computer Science Depart-ment at the University of Illinois atChicago. His current research focus-es on the design and assessment ofinteractive learning environments,
with an emphasis on advanced technologies and their rolesin the classroom. He received a BS from the University ofMichigan and a PhD from the University of Minnesota,both in computer science.
Stellan Ohlsson is an associateprofessor in the Department of Psy-chology at the University of Illinois atChicago. He received his PhD fromthe University of Stockholm in 1980.He was Senior Scientist at the Learn-ing Research and Development Cen-
ter in Pittsburgh before joining UIC in 1995. His researchis focused on the mechanisms for cognitive changes.
Mark Gillingham studies andsupports teachers and students whouse technology and the Internet. Hegraduated from the University of Wis-consin and is currently the educa-tional technology consultant to theGreat Books Foundation and the
Education Connection Network, for which he is developingonline discussion environments for adults and children.
Readers may contact Johnson at Electronic Visualiza-tion Lab, M/C 154, University of Illinois at Chicago, 851 S.Morgan St., Room 1120 SEO, Chicago, IL 60607-7053, e-mail [email protected].
IEEE
Virtual Worlds on the Internet
John Vince and Rae Earnshaw
The authors examine how the latestdevelopments in virtual environments,computer animation, communication networks, and the Internet are being configured to create revolutionary toolsand systems.
Contents: Data Flow Languages for ImmersiveVirtual Environments • VRML Interfaces forInformation Systems • VRML: A Designer’s View• Information Drill-Down Using Web Tools • Generic Uses of Real World Data in VirtualEnvironments • A Generic Functional Architecturefor the Development of Multi-User 3DEnvironments • Strategies for Mutability in VirtualEnvironments • Handling of Dynamic 2D/3DGraphics in Narrow-Band Mobile Services •Automatic Generation of Virtual Worlds forElectronic Commerce Application on the Internet
360 pages. 7" x 10" Softcover.January 1999. ISBN 0-8186-8700-2
