Toward a Model for Web–enhanced Problem–based Learning

Barbara Grabowski

Younghoon Kim

Tiffany Koszalka

Introduction

In this chapter, we merge the conceptual frameworks from two major projects funded by the National Aeronautics Space Administration (NASA)—Web-enhanced Learning Environment Strategies and Kids as Airborne Mission Scientists—to create a model for web-enhanced Problem–based learning (Grabowski, Koszalka, & McCarthy, 2000). This model is supported by and built upon research in two areas: (1) Problem–based learning (PBL) and the associated cognitive processes involved during learning, and (2) web-enhancement of classroom instruction. The intent of the model is to suggest a means for teachers, and to encourage them, to consider the richness of the Web in supporting PBL in their classrooms. Given that teachers, science teachers most notably, are resources-poor (O'Sullivan, Weiss, & Askew, 1998) and the Internet is resource-rich, this merger offers a very practical opportunity to capitalize on learning processes that research has shown to be effective for improving problem-solving ability, teamwork, communication skills, and interpersonal skills (Tan, 2002).

Web-enhanced Problem–based Learning Model

The model shown in Figure 1 conceptualizes web-enhanced Problem–based learning (W-PBL) within the current learning-centered paradigm (see, e.g., Reigeluth, 1999). The model is read from the inside out, with each ring identifying the factors and their attributes involved in a PBL event. Each area between the spokes represents a phase of the learning event that shows the interrelationship of the factors. The central feature of this model is the “learner as problem solver” (Tan, 2002). From this notion, every other part

emerges. The nine cognitive processes surrounding the learner are those stimulated in any independent or formal learning event (Gagne, 1985). The next ring brings the learning event into a formal classroom setting by defining four changing roles of the teacher engaged in a standard four-phased lesson. These lesson phases, as noted in the companion ring by the dotted circle (ring 4), are named by the web-enhanced learning environment strategies: frame, inform, explore, and try (Grabowski et al., 2000). Ring 5 overlays the teaching methodology—that of PBL—onto the framework. Finally, the types of web resources recommended for each phase flow from the last ring.

The teacher and learner move in tandem through the PBL stages. The responsibility of the learner remains as problem solver throughout, but the amount of control varies depending on the phase. A major assumption captured in the third ring is that the teacher serves in four different roles, determined by the phases of the learning event. In some cases, it is important for the teacher to take a leadership role, and at other times a less visible role. Using an arts metaphor, the teacher begins the learning event like a conductor. In this role, the teacher frames the lesson and selects the problem to be presented to the learners. The learners and the teacher work in tandem to develop an understanding of the problem. The teacher then moves into the role of stage crew, setting up a rich environment. The learners are able to assume a central role in deciding what they know and what they don't know and then planning how they will go about gathering the information in the next PBL phase of collecting information. When the learners begin the analysis phase, the teacher becomes a coach, guiding them through the experiments and analyzing their results. Finally, during the present-and-share-information phase, the teacher is a critic, providing important feedback to the learners.

A second important assumption of W-PBL is that the teacher in some situations, the learner in others, and both together in still other situations engage dynamically in selecting and using information from the Web to enrich the learning event and experience. Depending on the goal of the phase, they can choose from the varied sources on the Web. These sources are categorized into information and human resources, from a three-category taxonomy: site elements, organized sites, and networked resources. Site elements are resources that represent the raw materials from the Web. They include numbers, narratives, lists of references, still images, animations, video clips, sounds, and tools. Organized sites are resources that are generally developed with a specific purpose in mind, such as to entertain, present current or historical events, provide background information, instruct, or encourage hands-on activities. These resources include information, databanks, interactive events, current events, historical events, showcases, simulations, and tutorials. Networked resources are those that connect people electronically to enable shared interactions with experts, leaders, scientists, role models, and collaborators via e-mail, listservs, newsgroups, chat rooms, audioconferencing, and videoconferencing (Grabowski et al., 2000).

PBL and Cognitive Processing

The PBL model we selected has been well documented in the literature and is supported theoretically and empirically by other chapters in this book. The model in this chapter applies this foundational understanding and builds a rationale from this base.

PBL is a teaching methodology for posing realistic and interesting problem situations to learners. The methodology challenges learners to direct their own learning and resolve self-identified problems. Knowledge construction results from learners experiencing cognitive dissonance because of exposure to the problem scenario (Tan, 2002). By engaging in a variety of activities to understand and explore the identified problems, the learners attempt to reduce this dissonance and thus develop a deeper understanding of the knowledge domain.

PBL includes five key characteristics (Barrows, 1986, 1992; Hmelo & Evensen, 2000; Savery & Duffy, 1995; Schwartz, Brophy, Lin, & Bransford, 1999):

1. Real-world problems are used to set the learning context and act as a motivational driver for learners. These problems are used to help focus learners and stimulate them to get involved in the learning activity. The problems can be taken from actual or simulated scenarios.
2. Students set their own learning goals by questioning what they know and do not know about the problem scenario and then plan how to gather and learn the information relevant to solving the problem.
3. Multiple resources are provided for students to explore. These may include media, print, electronic, or human resources. With access to rich and varied resources, students can develop a deep understanding of the content related to the problem.
4. Students actively engage in problem solving through experimentation, data collection, reflection, collaboration, and communication with teachers, peers, and others who are key to investigating the problem. By being engaged in this way, students share their different perspectives and exhibit skills in reflective thinking, collaboration, and communication, which are essential for effective problem solving.
5. The teacher's role is that of a facilitator, to support the learning process and problem-solving activities rather than to directly teach what learners should know and how they should solve problems. However, we believe that, like a facilitator, the teacher's actions and visibility change based on the learning phase and the needs of the students, from conducting, creating a rich learning environment, coaching, to critiquing.

Much PBL research and evaluation has been conducted in diverse content domains, such as medicine, business education, social studies, and science. Most of the research, however, has focused on medical education, college or graduate school, and professional education settings. Some studies in medicine compared the effectiveness of a PBL program with conventional instruction. According to Hmelo and Evensen (2000), medical students who engaged in PBL were able to solve problems and transfer their learning better than students who studied under a conventional program. Albanese and Mitchell (1993) conducted a meta-analysis of the PBL literature from 1972 to 1992 and found that PBL helped medical students construct basic clinical and science knowledge and enhanced their reasoning skills when compared with a traditional instructional approach.

The research conducted in higher education and adult learning contexts prompted the development of PBL programs for middle and high schools. The Jasper Woodbury problem-solving series developed by the Cognition and Technology Group at Vanderbilt (1990, 1991, 1992) has been successfully implemented in middle school science and mathematics teaching. The Jasper series was based on anchored instruction with a PBL perspective and video-based programs. It was found to enhance students' construction of knowledge, transfer of problem-solving skills, and motivation. The use of an authentic problem in the Jasper series was especially powerful in promoting students' interest in and positive attitude toward mathematics and science learning.

Achilles and Hoover (1996) investigated middle and high school teachers' feedback from their PBL experience. In this study, teachers reported that PBL made learning more exciting and was a useful model for promoting students' communication and social skills, which were necessary for working with peers in a learning group. Faulkner (1999) reported that middle school science students who learned under a PBL model performed better in solving a near transfer problem than those who learned using worked examples. In addition, West (1992), studying the use of PBL in secondary school science classrooms, concluded that PBL could be an effective instructional strategy for stimulating students' interest in science, enhancing knowledge construction and problem-solving skills, and integrating science with other knowledge domains.

A five-phase PBL framework (Barrows, 1986, 1992; West 1992) drawn from these characteristics and research parallels the cognitive development processes (Gagne, 1985; Tan, Parsons, Hinson, & Sardo-Brown, 2003) that correspond to each learning event of the learning process (Gagne, 1985). These phases are set problem, plan, collect information, analyze, and present and share.

During phase 1, learners are presented with a problem scenario. The purpose of the scenario is to gain the learners' attention, thus activating sensory reception, the first stage in cognitive development. Without gaining and maintaining attention, there can be no learning (Keller, 1983). During phase 2, learners articulate what they know and do not know about the problem and create a plan for how to proceed. These tasks prompt learners to develop learning objectives that aid in solving the problem, thus activating expectancy control in cognitive processing. During phase 3, learners collect the information and study potential solutions to the problem as specified in the plan. Further, during phases 2 and 3, prior knowledge is retrieved that contributes to initial understanding of what is already known. Through activating selective perceptions, learners review multiple resources in an attempt to sort out the information and learn more about the problem as well as potential ways to solve it. Finally, as key information that is deemed relevant is found, learners encode it, that is, they organize the information in a way that is meaningful to them and that allows easy retrieval.

During phase 4, learners analyze the collected information, evaluate its usefulness to solving the problem, and draw conclusions. These tasks require learners to act upon the information they have learned, and the process activates the responding and reinforcing cycle of cognitive processing. Given the results of their experimentation, original ideas are reinforced or revised and new information is assimilated or tuned (Rummelhart & Norman, 1978). Finally, during phase 5, students are tasked with presenting their solutions and sharing their ideas with others, who may provide additional insights from different perspectives. These tasks activate retrieval of new knowledge in the context of the problem solution, retention of new knowledge, and, potentially, generalization of the new knowledge based on insights gathered from the different perspectives offered by the audience.

In summary, this five-phase PBL framework parallels the cognitive processing stages of reception, expectancy, retrieval, selective perception, encoding, responding, reinforcement, retention, and generalization during learning. The PBL process takes learners through the five learning stages, each of which activates cognitive processing and therefore prompts learning. Thus, well-designed and well-executed PBL environments encourage learners to develop a deep understanding of a knowledge domain while they practice and develop problem-solving skills (Duffy & Cunningham, 1996; Hmelo & Evensen, 2000).

Web-enhanced Learning Environment Strategies (WELES) and PBL

Today, Internet technology enables the integration of web resources into classrooms to enhance the interactive and social nature of instruction. In recent years, researchers have investigated Internet, intranet, and extranet interactive learning strategies (Geyer, 1997), interactive collaboration with scientists (Federman & Edwards, 1997), electronic discussion groups (Karayan & Crowe, 1997; Papert, 1997), multiuser object-oriented virtual spaces for sharing ideas and developing solutions to problems (Conlon, 1997), electronic learning communities (Lieberman, 1996), and general use of Internet resources in the classroom (Koszalka, 1999). This field of research is rich. Findings suggested that these interactive and technology-enhanced learning strategies engaged learners more fully in instruction and facilitated their ability to comprehend and to construct personal knowledge. Evidence also showed that the use of Internet technologies in the classroom promoted openness, sharing, and involvement in students' own learning;raised academic achievement; helped the development of social skills; aided in the mainstreaming of handicapped students; reduced ethnic tensions;increased self-esteem; and predicted students' interest in science careers (Kagan & Widaman, 1987; Koszalka, 1999; Sharan & Kussell, 1984; Slavin, 1983). These studies have demonstrated that the possibilities for web use in the classroom extend far beyond the individualized drill-and-practice and entertainment scenarios of the past.

Just because web resources can be used, or have many possibilities for use in schools, it does not mean that they will be. Recent statistics showed that, although upwards of 98 percent of schools in the United States were reported to be wired for some type of Internet access and over 70 percent of classrooms had Internet connections, only 21 percent of educators acknowledged using the Internet to a small extent and 31 percent to a moderate or large extent with their students (National Center for Educational Statistics, 2000a, b). One reason might be that more technology funds in schools are being spent on equipment rather than on supporting educators' professional development and efforts to create learning environments that integrate such resources into teaching and learning (Department of Education, 2000; Ronnkvist, Dexter, & Anderson, 2000). Supporting educators' professional development in technology integration may provide a key to increasing the incorporation of technology resources into teaching practices and learning environments. Implementing interventions that are flexible and are able to help a variety of educators adopt these new technologies in their own classrooms is crucial.

The WELES reflection tool, shown in Figure 2, provides educators with a road map through the myriad of resources available on the Web, as well as a framework for reflecting on how these different types of resources may be used with six methods of teaching using four key lesson strategies. The resulting four central WELES follow a typical lesson sequence: framing a lesson; informing learners; providing for content exploration by learners;and allowing learners to try out newly acquired skills, knowledge, and inclinations. This reflection tool, along with an accompanying lesson planner, is provided to educators as an overview of the conceptual interrelationship between teaching methodology and web resource categories. Educators can often see from this overview a broader conception of how the Web can be integrated into their classroom teaching. For example, a sixth-grade earth science teacher who prefers a presentation teaching method to frame lessons and motivate students may choose to present a series of web-based pictures and video clips of erupting volcanoes to his or her students to begin a lesson on volcanology. A high school physics teacher who prefers hands-on active learning may find a velocity and motion simulation for his or her students to use during the exploration of motion principles.

The WELES tools were run through a validation process with several experts in instructional design and educational technology, modified, and then used with over 359 teachers in 23 states of the United States and in Thailand. Findings suggested that the final version of the WELES reflection tool and lesson planner was representative of the most common pedagogic approaches and technology integration strategies, helped educators think about using web resources to enhance their teaching, increased the use of Internet resources among educators who were trained in using the WELES tools, and led to greater use of different types of Internet resources in multiple subject areas using multiple methods of teaching. Thus, WELES helped educators operationalize the use of web-based resources within their

technology-enhanced classrooms, based on their teaching preferences, resource and curriculum needs, and existing technology configurations (Grabowski & Koszalka, 2000).

The W-PBL model extends the merger of teaching method and resources to identify the type of web resources that would most likely enhance the various phases of the PBL experience, as summarized in Table 1. When setting the problem, there can be two types of problems: real-world and simulated (Tan, 2002). The resources for a real-world problem are most likely to come from organized sites containing current or historical events. These sites contain contexts that are entirely real. In these cases, learners solve the problems in a similar manner as experts would in the real situations. For a simulated problem, teachers have at their fingertips all types of site elements. They can gain immediate and easy access to authentic numbers, video and sound clips, animations, narratives, images, and tools to make the problem feel real.

In the planning phase, learners collaborate among themselves to assess what they themselves already know. In this case, there is no need for web resources. However, to complete the phase, the teacher, as coach, helps them refine their ideas to determine their plan of action. At this point, collaborators or experts accessible through networked web resources would serve a useful function. Once their plan of action is created, there is no limit to the possibilities of resource acquisition through the Web. Learners should be encouraged to seek out site elements, organized sites, and networked resources to collect relevant information and data.

In the data analysis phase, learners can seek out web tools (site elements), simulations from organized sites, and experts and other collaborators in order to interpret all of the information they have gathered. Finally, the Web offers one of the richest opportunities to present and share solutions beyond the classroom—through showcases designed specifically for this purpose. Feedback can be sought from experts and other collaborators through networked resources.

W-PBL Exemplified in KaAMS (Kids as Airborne Mission Scientists)

KaAMS, a NASA-funded development and research project, was designed using a W-PBL approach. From research on PBL, we selected four phases for the learning event as shown in Figure 3 and created web-enhanced lesson plans to guide teachers' use of this process. Using KaAMS lesson plans, teachers present a real problem and coach students through the mission as scientists as they participate in “bursts” of interactive activities culminating in the analysis of data from real NASA airborne missions.

This project was realized by connecting and organizing a variety of existing web-based learning resources for teachers to use with their middle school students. With the KaAMS PBL model as a guide, four modules addressing two different environmental missions—active lava flows and the health of coral reefs in Hawaii—were developed. These missions were selected because NASA data already existed for studying the problems. In addition, the topics matched well with middle school curricula, national standards, and middle school student interests.

KaAMS Phase 1: Present Problem Scenario

In phase 1, students are presented with the problem scenario. Learning is framed by the context of one of the authentic, real-world problems noted above to gain students' attention and to motivate them to get involved immediately (Cognition and Technology Group at Vanderbilt, 1990, 1991, 1992; Duffy & Cunningham, 1996). This is the frame phase. In the first mission, concerning active lava flows in Hawaii, students are put in the role of airborne remote sensing scientists charged with identifying where the active lava flows are located on the Kilauea volcano. The KaAMS development team created this simulated mission from several web site elements related to volcanoes, active lava flows, and information about the Pacific Disaster Management Agency. The teacher selects this mission and begins the learning event by showing students a web-based letter requesting assistance from the Pacific Disaster Management Agency (see Figure 4). The problem scenario prompts students to explore the overall problem by having them develop an understanding of key concepts such as aeronautics, remote sensing, and airborne remote sensing. It also provides students with a sense of being airborne mission scientists who use aeronautics principles and remote sensing data to study an environmental problem of the earth. At this point, students obtain clarification about the problem from their teacher.

KaAMS Phase 2: Propose Ideas and Search for Information

During learning phase 2, students propose ideas and search for information. This is the inform phase, or the planning and gathering information phase of PBL. The PBL literature posits that students should create their own learning goals and be provided with access to multiple learning resources (Duffy & Cunningham, 1996; Savery & Duffy, 1995). Therefore, students are encouraged to explore rich and varied existing NASA web resources to

find the basic science necessary to solve the problem. They are asked to create a plan of study that will help them clarify issues surrounding the problem and plan for conducting a NASA mission to gather data to help them solve the problem. To support these learning activities, all types of web resources, such as information, still images, video clips, and databanks of NASA aircraft, remote sensing, and volcanoes are provided to students. A lesson plan within this phase also presents web resources related to a variety of learning activities for students to develop an understanding about who airborne mission scientists are, how they explore the world, and how these scientists work together (see Figure 5).

KaAMS Phase 3: Collect and Analyze Data

Another key characteristic of PBL is that students actively explore, experiment, analyze, and interpret information (Barrows, 1986, 1992). The third and fourth PBL phases are combined in KaAMS into one explore phase: conducting the mission. After searching for information and

developing an understanding of the problem, students are given an opportunity to select which NASA aircraft they will use to run their mission to collect actual data (see Figure 6). They are prompted to think about how data can be collected using airborne remote sensing aircraft. To support students' learning in this phase, web resources related to NASA aircraft and several simulations or hands-on activities, such as flying a kite, developing film, and analyzing data images, are provided to students.

After collecting the data, students can participate in numerous activities to learn how to analyze and interpret both visible and infrared remote sensing images. To support these learning activities, visually rich NASA web-based remote sensing images and web-based guidelines developed by NASA

scientists are provided. Students then analyze and interpret two actual NASA images of the Kilauea volcano to locate the active lava flows.

KaAMS Phase 4: Propose Solutions

In the last phase, students try out their knowledge by proposing solutions in a public forum (Go Public) (Schwartz et al., 1999). This is the try phase. After analyzing and interpreting the data, students write the results of their investigation for the KaAMS mission to locate active lava flows on Kilauea (see Figure 7). Each student group presents the best solution and shares it with the other students and teachers. After all the solutions are presented,

students have an opportunity to revise their solutions based on feedback from their peers, teachers, and experts before making their final statement. With this final statement, they complete their investigation and mission.

Plans for the KaAMS site include developing a showcase interface for students to post and display their solutions and a NASA network interface that facilitates communication between students and NASA scientists.

Conclusion

A model for W-PBL merges the role of learner as problem solver and four roles of the teacher in the five phases of a PBL process. The interrelationships between the learners, their cognitive processes, teachers, learning events, and the PBL phases determine which types of information or human web resources are the most likely sources for lesson enhancement. The W-PBL model is supported by and built upon research in PBL, cognitive learning processes, and web-enhancement of classroom instruction. The model suggests a means for teachers, and encourages them, to consider the richness of the Web in supporting PBL in their classrooms.

Acknowledgments

These projects were made possible through funding from the NASA Dryden Flight Research Center and the NASA Leading Educators to Applications, Research, and NASA-related Educational Resources in Science (LEARNERS), a Cooperative Agreement Notice from the NASA Education Division and Learning Technologies Project, project number NCC5-432: Learning Using ERAST Aircraft for Understanding Remote Sensing, Atmospheric Sampling and Aircraft Technologies (LUAU II). In addition, we acknowledge a multitude of individuals who have contributed to this project, especially Dr. Marianne McCarthy, Education Officer from the NASA Dryden Flight Research Center, and Dr. Luke Flynn of the University of Hawaii, Department of Geophysics.

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