Problem-based learning

Introduction

Problem-based learning (PBL in this article) is defined by Finkle and Torp (1995) as, “a curriculum development and instructional system that simultaneously develops both problem solving strategies and disciplinary knowledge bases and skills by placing students in the active role of problem solvers confronted with an ill-structured problem that mirrors real-world problems”.

What is PBL?

Problem-based learning is an instructional design model and a variant of project-oriented learning. It is closely related to inquiry-based learning.

Real-life problems seldom parallel well-structured problems; hence, the ability to solve traditional school-based problems does little to increase relevant, critical thinking skills. Real-life problems present an ever-changing variety of goals, contexts, contents, obstacles, and unknowns which influence how each problem should be approached. To be successful, students need to practice solving ill-structured problems that reflect life beyond the classroom. These skills are the goal of PBL. With Problem-Based Learning, students engage in authentic experiences.

PBL is inherently social and collaborative in methodology and teaches students essential "soft skills" as well as domain specific content and skills. PBL is learner-centered and gives the learners progressively more responsibility and independence in their education. It encourages life-long learning. In PBL, it is the problem that drives the curriculum. It does not test a skill, it assists in the development of the skill itself. There is no one solution: the problem is solved in an iterative process where the perception of the problem can change as do the solutions found.

What Skills do Students learn?

Through PBL, students learn:

• Solving real-life problems: Learning to solve relevant and contextual problems congruent with workplace skills, develop initiative, performance ability and enthusiasm.

• Efficient problem solving: Develop the ability to find and use appropriate resources for problem solving

• Independant learning: Employ effective self-directed and self-motivated learning skills and proactive thinking to continue learning as a lifetime habit

• Self-monitoring: Continuously monitor and assess the adequacy of their own knowledge and of their problem-solving skills, practice critical thinking (see also cognitive tools)

• Team work: Efficient collaboration as a member of a group, communication and leadership skills, social and ethical skills.

From the problem based learning initiative of the southern illinois university and the Stanford site on PBL

Historical Background

Problem-Based Learning (PBL) has become popular because of its benefits to student learning.

PBL can be thought of as a combination of cognitive and social constructivist theories, as developed by Piaget and Vygotsky, respectively. The first application of PBL was in medical schools which rigorously test the knowledge base of graduates. According to García-Famoso (2005), “PBL was first applied in the 60s, in the Faculty of Health Sciences of McMaster University (Canada) and in the School of Medicine of Case Western Reserve University (United States). The main objective was twofold: to develop problem solving skills and bring learning closer to real medical problems.” After these first experiences, many medical and professional schools started to use some form of PBL, for example, Harvard Medical School or, in Europe, Maastrich University. Many medical and professional schools, as well as undergraduate and graduate programs, use PBL in some form. Over 80% of medical schools use the PBL methodology to teach students about clinical cases, either real or hypothetical (Vernon & Blake, 1993, Bridges & Hallinger, 1991).

Models of PBL, Designing PBL curricula

Models of PBL

There are many problem-based learning models. E.g. Edwin Bridges (1992) suggests that there are two versions of PBL that have been implemented in the classroom, problem-stimulated PBL and Student Centered PBL.

Problem Stimulated PBL (PS PBL)

PS PBL uses role relevant problems in order to introduce and learn new knowledge.

PS PBL emphasizes 3 major goals:

• development of domain-specific skills
• development of problem-solving skills
• acquisition of domain-specific knowledge

Student Centered PBL (SC PBL)

SC PBL has the same goals as PS PBL, but includes one more: fostering life-long learning skills. Physicians are one group of professionals who are required to stay current with new developments in their fields. The skills of a life-long learner are particularly important for this group. Hence, several medical schools employ student centered PBL.

The major differences with PS PBL are in student responsibilities. In SC PBL:

• students themselves identify the learning issues they wish to explore
• students determine the content to be mastered
• students determine and locate the resources to be used

In short, students have self-defined learning issues. As is the case with PS PBL, students decide how to appropriately use the newly acquired information and knowledge in order to solve the problem at hand.

Case-based PBL See learning by design. The typical sequence of activities in a Learning-by-Design unit has students encountering a design challenge and attempting a solution using only prior knowledge. Students compare and contrast their ideas, identify what they need to learn to move forward in addressing the design challenge, choose a learning issue to focus on, and design and/or run a laboratory activity to examine that issue. Following this are cycles of exploratory and experimental work.Kolodner, Crismond, Gray, Holbrook & Puntembakar (1998)

Designing PBL

Integrating PBL into a Curriculum

Design Considerations:

• How should PBL be incorporated into the curriculum?
• What problems should be used and how should they be presented?
• What are the instructional goals?
• How should small groups be formed?
• How much should each problem be prestructured?
• How to evaluate the program and the students?
• What resources should be available?
• How to prepare students and faculty for PBL? (Bridges, 1992).

Creating appropriate Problems

PBL problems should be created with :

• introduction
• content
• learning objectives
• resources
• expected outcome
• guiding questions
• assessment exercises
• time frame

(Bridges, 1992)

The best format for problems is unorganized, unsynthesized, and open-ended because this allows for student processing. Students are motivated to use their reasoning skills and relate the content to their own context and previous knowledge. Focus problems on current events, student lives, or relationships to actual occurrences. Problems should be interdisciplinar and task oriented. It should not only focus on the large problem but also take students through the objectives. (Albanese & Mitchell, 1993)

Novice learners require more structure and cues while more experienced students are self-directed learners. Software can be used in the PBL curriculum, but avoid telling students when the solution is reached. This stops the learning process. Point out inappropriate strategies. Complex problems usually require learners to exhibit management, research, and thinking skills that help distinguish less expert from more expert performers. This differentiation can help serve as a grading standards in the class.(Albanese & Mitchell, 1993)

Getting Started

• Anticipate and manage anxiety (Bernstein, Tipping, Bercovitz, & Skinner, 1995).
• Explain to all involved what is happening and why.
• Tutors should receive training (Foley, Levy, Russinof, & Lemon, 1993).
• Students should be oriented to PBL.
• State the PBL goals.
• Randomly assign students to PBL (Mennin Friedman, Skipper, Kalishman, & Snyder, 1993).

According to Schmidt and Moust (1989), the student progresses through a series of steps, "The Seven Jump", during the PBL process.

1. Clarify unknown terms and concepts in the problem description.
2. Define the problem(s). List the phenomena or events to be explained.
3. Analyze the problem(s). Step 1. Brainstorm. Try to produce as many different explanations for the phenomena as you think of. Use prior knowledge and common sense. Student outcomes: activation of prior knowledge, elaboration, restructuring of information, organization of information, intrinsic motivation (see also Flow theory, Motivation).
4. Analyze the problem(s). Step 2. Discuss. Criticize the explanations proposed and try to produce a coherent description of the processes that, according to what you think, underlie the phenomena or events.
5. Formulate learning issues for self-directed learning.
6. Fill in gaps in your knowledge through self-study.
7. Share your findings with your group and try to integrate the knowledge acquired into a comprehensive explanation for the phenomena or events. Check whether you know enough now. Student outcomes: restructuring, applying, problem solving.

Evaluation

Because instruction and learning is different in problem based settings than traditional instruction, many instructors find student evaluation difficult.

PBL encourages development of meta-cognitive skills like group learning or research and communication skills and aims transferring knowledge to novel situations. With such multiple purposes for PBL, it is important to consider a variety of evaluation techniques:

• Written examinations: should be designed to ensure transference of skills to similar problems or subject domains.
• Practical examinations: used to ensure that students are able to apply skills learned during the course.
• Concept maps: much of the learning that goes on during PBL is more than just a compilation of facts. As such, written examinations may not be an adequate measure of student growth. Requiring students to generate concept maps, in which they depict their knowledge through the creation of identified nodes and links, may present another option to determine their cognitive growth.
• Peer assessment: because life outside the classroom usually requires working with others, peer assessment is a viable option to measure student growth. Providing students with an evaluation rubric often helps guide the peer evaluation process. This process also emphasizes the cooperative nature of the PBL environment.
• Self assessment: an important element of PBL is to help students identify gaps in their knowledge base in order for more meaningful learning to result. Self assessment allows students to think more carefully about what they know, what they do not know, and what they need to know to accomplish certain tasks.
• Facilitators/tutor assessment: the feedback provided by tutors should encourage the students to explore different ideas. It is important that facilitators do not dominate the group and facilitate learning and exploration. Tutor assessment may consist of how successful individuals interacted with their group and their cognitive growth.
• Oral Presentations: because so much of work life revolves around presenting ideas and results to peers, oral presentation in PBL provide students an opportunity to practice their communication skills. Presenting findings to their group, the class, or even a real-life audience can help strengthen these skills.
• Reports: Written communication is another skill important for students. Requiring written reports allows students to practice this form of communication.

Evaluation is an iterative process. Be prepared to make changes along the way based on experience (Bernstein, Tipping, Bercovitz, & Skinner, 1995).

Ressources

Ensure resources and time are available for self-study. "If students are to be genuinely empowered with their own learning, it is important to provide them with the necessary infrastructure." (Rangagachari, 1991). PBL students study in the library more than conventional students and study more during the day than the evening. Increasing the time spent instructing students decreases the time students spend in self-study (Williams, Saarinen-Rahikka, & Norman, 1995). If students must learn basic science or similar material for national standardized examinations, increase student access to self-assessment, provide practice examinations, allow additional examination preparation time (Mennin et al., 1993).

See also Problem-based learning and electronic games

Roles in PBL

Instructor's Role

Teaching in PBL normally occurs within small discussion groups of students facilitated by a faculty tutor (Aspy, Aspy, & Quimby, 1993, Bridges & Hallinger, 1991, Mayo, Donnelly, Nash, & Schwartz, 1993). Because the amount of direct instruction is reduced in PBL, students assume greater responsibility for their own learning. The instructor's role becomes one of subject matter expert, resource guide, and task group consultant. This arrangement promotes group processing of information rather than an imparting of information by faculty (Vernon & Blake, 1993). The tutor is most active in planning the PBL, the content and sequence of projects. He encourages student participation, provides appropriate information to keep students on track, gives immediate and appropriate feedback, and assumes the role of mentor, tutor or fellow learner (Aspy et al., 1993). The tutor acts as metacognitive coach, serving as model, thinking aloud with students and practicing behavior he wants his students to use (Stepien and Gallagher, 1993. He also evaluates the students.

Student's Role

The individual student in PBL

In PBL, students have responsibility for their own learning by identifying their learning issues and needs.

The students work with the following learning materials:

• the problem situation
• a list of objectives that the student is expected to master while working on the problem
• a reference list of materials that pertain to the basic objectives
• questions that focus on important concepts and applications of the knowledge base.

Time allotted to each project is fixed. Students work on the problem in project teams. Students are evaluated in multiple ways by instructors, peers, and self, using questionnaires, interviews, observation, and other assessment methods.

Groups in PBL

Students work in teams to complete the project, resolve the problem, and accomplish the learning objectives.

Groups usually consist of 5 to 7 students. Four roles are possible:

• project leader - proposes meeting agendas, suggests division of labor, and develops the overall project plan.
• facilitator - describes the process to be followed during the steps of the project plan, determines appropriate time to proceed in plan, and suggests adjustments to the plan as needed.
• recorder - takes group notes of each meeting.
• team member - takes individual notes, participates in discussion, and reviews resource materials.

Some PBL models include a mentor or tutor in the group (often a faculty member, or another student).

The team schedules its own activities and decides how to use the allotted time

See also Problem-based learning and social software

Discussion

Application of PBL: Advantages, Disadvantages

Advantages

Why is there an increase in scores resulting in PBL? Information theory links 3 conditions to subsequent improved retrieval and use. Bridges & Hallinger (1991) report that students improve their comprehension because they:

1. are better at activating prior knowledge,
2. learn in a setting resembling their future context, and
3. elaborate more fully on the information presented.

Increased elaboration promotes mental processing, understanding, and recall. Because content is learned in context, definitions, information, theories, correlations, and principles are learned and integrated with one another (Mandin, Harasym, & Watanabe, 1995).

See also the learning level article.

The Buck Institute fro Education (BIE) sees PBL as a mean of developping what they call 21st century skills, meaning

• ICT literacy
• cognitive skills like critical thinking, creativeness
• Interpersonal skills
• Self- and task-managment skills
• personal charcteristics like ethical sensibility, civic responsibility, accountability

Disadvantages

Introducing PBL means

• changing the Curriculum
• introducing higher costs
• higher time demands: PBL takes more time to teach the same content
• change of roles: Students have to change attitude and go from memorization of facts to an active searching for information(Reithlingshoefer, 1992). Teachers have to shift from dissemination of information to a tutor's and guide role.
• formulation of appropriate problems that encompass both a large goal and specific objectives
• setting up appropriate assessment
• facing a lack of extrinsic rewards for PBL teaching

Is PBL better?

When determining the value of PBL curriculum, the literature has focused on 4 components :

• Attitudes: Students enrolled in PBL courses appear to have a more favorable attitude toward their course than students schooled in traditional instruction. Improved attitudes contribute to a variety of factors including increased course enrollment, enhanced interest in major course of study, and positive feedback from faculty and employers (Pincus, 1995); a reduced dropout rate (Bridges & Hallinger, 1991; Pincus, 1995); and an increase in student comments concerning the advantages of PBL after their learning experience (Bernstein, Tipping, Bercovitz, & Skinner, 1995). Schmidt, Henny, and de Vries (1992) conclude that "problem based curricula do appear to provide a friendlier and more inviting educational climate."

• Basic knowledge: Test results seem split on basic knowledge comprehension. In the medical field, although it was sometimes found that students schooled with PBL performed worse on standardized tests, they performed better on clinical tests and equal on essay tests to conventionally-schooled students (Albanese, 1993). Not all studies are favorable to PBL, but Albanese found that PBL knowledge is more deeply ingrained and less likely to be forgotten.

• Problem solving ability: Reasoning and problem solving skills: The evidence appears supportive in finding PBL students better than conventional students in analyzing atypical medical cases (Albanese, 1993), and in having stronger problem solving skills (Gallagher, Stepien, & Rosenthal, 1992).

• Study habits: Team work Most PBL is done in small groups. Therefore it is not surprising to find that students who learn in this context tend to be more oriented toward collaborative learning.

Examples and links

Examples

• Medicine Blends Computers and PBL

• Ace Training Ltd. A complete Case Study of Problem-based learning

• Examples of PBL from the Stanford Learning Laboratory.(find examples of PBL at university Level, in biology, environmental sciences, high School level, economics, environmental sciences, history, ancient worlds and english).

University level

• Biology

• Teacher Training in Science

Sherman Rosenfeld and Yehuda Ben-Hur, PBL in Science and Technology: A Case Study of Professional Development, Department of Science Teaching, Wizmann Institute of Science

• Problem-Based Learning at McMaster University (Canada).

High School Level

• History

• Ancient World

Commercial PBL example cases

• Ace Training Ltd. A complete Case Study of Problem-based learning

Various links

• Problem-based learning and electronic games

• Problem-based learning and social software

• Problem-based Learning resources page with a comprehensive list of links of the technology for learning consortium.

• Problem-Based Learning comprehensive site of the Illinois maths and science academy with description of pbl, rersources, examples and more.

• Problem-based learning pages in the archives of the center for teaching, learning and scholarship from the samford university, alabama, previously center for problem-based learning

• Problem-Based Learning pages of the learning-theories.com site: knowledge base and webliography.

• pennsylvania state university and nasa wiki-like page on pbl

• very complete pbl site of the university of delaware.

• PBL pages of the maricopa center for learning and instruction MCLI, arizona with a searchable archive.

• resources site from the queensland university

Journals:

• The Interdisciplinary Journal of Problem-based Learning (IJPBL) is an open access journal that publishes relevant, interesting, and challenging articles of research, analysis, or promising practice related to all aspects of implementing problem-based learning (PBL).

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