Empirical Research

Problem-Based Learning/Instruction

Reference:

Kaufman, A. (ED.) (1985). Implementing Problem-Based Medical Education. New York: Springer.

Introduction/Purpose:

Problem-Based Learning (PBL) is an instruction strategy where students solve realistic problems and decisions people face every day. It fosters the development of self-directed learning strategies. It also makes it easier for students to retain knowledge and apply knowledge and strategies to new situations. In PBL, teachers coach students with suggestions but do not assign predetermined learning activities. However, the students pursue their own problems solutions. Students get into groups and solve the same problem in different ways and arrive at different answers. The purpose of the study was to determine the effectiveness of PBL compared to traditional instructional approaches in developing high school students’ macroeconomics knowledge. It was also to examine whether PBL was effective with students with different levels of verbal ability, interest in economics, preference for group work, and problem solving efficacy.

Research Hypothesis:

This study tested three hypotheses:

There is no difference in achievement, as measured via pretest-posttest changes in macroeconomics knowledge, between students

in PBL and traditional instructional environments,

with different levels of verbal ability in PBL and traditional classes, and among students with different levels of interest in learning economics, preference for group work, and problem-solving efficacy.

Method/Setting/Populations/Participants/Research Subjects:

-There were five veteran teachers that participated in this study. They were from four different high schools which were all located in a large metropolitan area in Northern California. Two of the high schools were suburban and two were urban. The study was conducted in the spring of the 1999-2000 academic year. The teachers in the study all taught the same macroeconomics content using a PBL approach with one or more classes and a traditional lecture/discussion approach using one class. They were allowed to select which class they taught during the lecture/discussion approach before they saw their class list. There were 346 twelfth graders in eleven classes that completed one or more of the instruments that were used in the study.

-Independent –sample tests were used to examine if students in the PBL and traditional classes showed significant differences in their verbal ability, interest in learning economics, preference for group work, and problem solving efficacy. The test that measured macroeconomics knowledge used 16 four part multiple choice items from the Test of Economic Literacy. The items addressed the full range of cognitive objectives from Bloom’s Taxonomy. Items on the test required students to demonstrate their understanding of inflation, unemployment, and gross domestic product.

Procedures:

Students worked in groups to clarify the nature of a problem and determined what economic concepts and relationships were necessary to solve the problem. Then they worked in groups and did research in order to understand economic theories. At the end, the students gave a presentation of their different solutions and their teacher asked them questions to determine if they truly understood economic concepts and principles. One student gave the speech but the questions were addressed to all group members.

Results/Findings:

The independent sample tests on the pretest and posttest change on the macroeconomics tests were calculated to determine if there was a significant difference in the learning of macroeconomic concepts between students in the PBL and traditional classes. Students in the traditional class gained more in macroeconomics knowledge than students in the PBL class, even though it was not significant. This indicated that the first hypothesis was rejected and that the PBL instructional approach was more effective than the traditional approach in helping students to learn basic macroeconomic concepts.

Discussion/Conclusions/Recommendations:

-The rejection of the first hypothesis was a compelling finding, especially since there was such a very small difference. Across all teachers, PBL classes gained .66 or 4% more than the traditional classes. Educators are encouraged to experiment with PBL. Also, students with different characteristics perform differently within PBL and lecture/discussion classes. Students whose verbal ability was mid-range and below learned more in the PBL classes than they did in the lecture/discussion classes. In this area, slightly more students learned more in the PBL classes.

-In addition, instructional approach affects students differently according to their interest in learning economics. Lecture/discussion students most interested in learning economics showed little change in mean content knowledge between pretest and posttest. However, PBL students with the same level of interest in learning economics showed a significant gain in content knowledge.

-Students with high efficacy in problem solving learned more in PBL classrooms.

-The preference for group work was extremely small in both the PBL and lecture/discussion approaches. Students may prefer working by themselves or with others.

-Overall, PBL was found to be a more effective instructional approach for teaching macroeconomics than traditional lecture/discussion, even though the percentage was very small. Also, PBL was more effective than traditional instruction with students of average verbal ability and below, students who were more interested in learning economics, and students who were most and least confident in their ability to solve problems.

Implications to Education/My Reaction to the Study

            My hypothesis was correct in this study in that problem based learning (PBL) would be more effective in teaching macroeconomics than the traditional lecture/discussion approach. I assumed this for a number of reasons. First, I thought that a student could learn more by working with others because two, three, or four brains are stronger and wiser than one. So based on this alone, I figured PBL would be more beneficial to the students. Secondly, during PBL, students are allowed to conduct research and formulate their own solutions and strategies to problems. To me, this could be much more effective than sitting and listening to someone lecture.  Third, each member of the group provides a different approach to gathering information and provides different responses. During a lecture, students have to go by what the lecturer is saying. So based on all this, I speculated that the PBL approach would be more effective, and it proved to be just that.

            I was not sure which approach would be more effective with students of average verbal ability and below, students who were more interested in learning economics, and students who were most and least confident in their ability to solve problems. After my research, I learned that PBL was more effective in all of these areas, compared to the traditional lecture/discussion approach. Because of these findings, I believe that all teachers should incorporate the problem based learning approach in their classroom.