Scholarly article on topic 'The Effectiveness of Problem-based Learning Supported with Computer Simulations on Reasoning Ability'

The Effectiveness of Problem-based Learning Supported with Computer Simulations on Reasoning Ability Academic research paper on "Economics and business"

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{PBL / "Elementary Science Education" / "Buoyant Force in Fluids and Gases" / "Reasoning Ability"}

Abstract of research paper on Economics and business, author of scientific article — Özlem Koray, Abdullah Koray

Abstract The purpose of this study was to investigate the effectiveness of Problem Based Learning (PBL) supported by interactive computer simulations within the context of “Buoyant Force in liquids and gases” subject on reasoning ability. The study was conducted with a quantitative methodology via non-equivalent groups quasi-experimental design. The sample of 54 students enrolled in two eighth grade classes of a public middle school in Turkey was included in this study. One of these classes was randomly assigned as experimental group and instructed by means of PBL, whereas the other class was assigned as control group and instructed by means of traditionally designed instruction. In order to measure reasoning ability of the students, The Test of Logical Thinking was used as pre- and post- tests in both control and experimental groups. The results of independent t-test showed that the students in PBL classes had significantly higher mean scores on reasoning ability than the students of control group.

Academic research paper on topic "The Effectiveness of Problem-based Learning Supported with Computer Simulations on Reasoning Ability"

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Procedia - Social and Behavioral Sciences 106 (2013) 2746 - 2755

4th International Conference on New Horizons in Education

The effectiveness of problem-based learning supported with computer simulations on reasoning ability

Ozlem Koraya*, Abdullah Korayb

aBulent Ecevit University, Eregli Education Faculty, D epartment of Primary Education, Kdz.Eregli,67300 Zonguldak, Turkey. hBulent Ecevit University, Eregli Education Faculty, D epartment of Primary Education, Kdz.Eregli, 67300 Zonguldak, Turkey.


The purpose of this study was to investigate the effectiveness of Problem Based Learning (PBL) supported by interactive computer simulations within the context of "Buoyant Force in liquids and gases" subject on reasoning ability. The study was conducted with a quantitative methodology via non-equivalent groups quasi-experimental design. The sample of 54 students enrolled in two eighth grade classes of a public middle school in Turkey was included in this study. One of these classes was randomly assigned as experimental group and instructed by means of PBL, whereas the other class was assigned as control group and instructed by means of traditionally designed instruction. In order to measure reasoning ability of the students, The Test ofLogical Thinking was used as pre- and post- tests in both control and experimental groups. The results of independent t-test showed that the students in PBL classes had significantly higher mean scores on reasoning ability than the students of control group.


Selectionandpeer-reviewunderresponsibilityofThe AssociationofScience,EducationandTechnology-TASET,SakaryaUniversitesi, Turkey.

Keywords: PBL, Elementary Science Education, Buoyant Force in Fluids and Gases, Reasoning Ability.

1. Introduction

Continuous change occuring in today's world has been forcing educational systems to change. The changes in educational systems have caused replacement of common approaches of education in which students are dependent on books and teachers, and want to get too much knowledge by rote learning, with modern approaches of education. In modern educational point of view, students must be heartened to go beyond the memorization of facts, to think critically and creatively, and to apply their knowledge to problem solving in new and unfamiliar contexts (Chin & Chia, 2006). To provide required changes in line with modern education approaches,

* Corresponding author. Tel.: +90-372-323-3870 (110); fax: +90-372-323-8693. E-mail address:

1877-0428 © 2013 The Authors. Published by Elsevier Ltd.

Selection and peer-review under responsibility of The Association of Science, Education and Technology-TASET, Sakarya Universitesi, Turkey. doi:10.1016/j.sbspro.2013.12.315

constructivist theory has been providing a well-established guide. The constructivist theory accepts that students need to be exposed to learning experiences that enable them to construct their own knowledge and promote their thinking skills (as cited by Barak et al, 2007 from Cobb, 1994 and Driver, Asoko, Leach, Mortimer, & Scott, 1994).

Among methods based on contructivist approach, problem based learning has been providing an important opportunity to improve active learning and higher order thinking skills including critical thinking, creative thinking and problem solving (Kumar, 2010; Tan, 2007; Barak et al, 2007). Problem-based learning has been developed in the late 1960s at McMaster Medical School in Canada and pervaded since then throughout different parts of the world. PBL has also been integrated into other medical schools and health-related programs such as nursing, dentistry and therapy (Mierson, 1998, Scott et al., 1999, Solomon & Geddes, 2001). Futhermore, it has been adopted by numerous disciplines including architecture, law, engineering, business, social work (Savery & Duffy, 1995), geography (Bradbeer& Livingstone, 1996), zoology (Harland, 2002), biology (Chin & Chia, 2004), chemistry (Yee, 2007) and science education (Gallagher et al.,1995, Dahlgren & Oberg, 2001, Kumar and Sherwood, 2007).

Problem-based learning is an instructional method characterized by use of problems as a context for pupils, working in small groups, to learn problem-solving skills and to enhance their knowledge (Albanese & Mitchell, 1993). Learning in this way is oriented and self-motivating and pupils learn while searching for solutions to problems. They are actively involved in process and learn in the context in which knowledge is to be used (Chin & Chia, 2004). Kolodner et al. (2003) also indicated that, in a PBL process, students learn by solving real-world problems and reflecting on their experiences because real-world problems are complicated, students work together in groups where they pool their expertise and experiences together and cope with complexities of issues that must be considered. In PBL, information that students collect about unit ofstudy is learned for the purpose of solving a problem. Therefore, problems are introduced at the beginning of a unit of instruction. This order is different from traditional teaching methods which present problems only after students have learned the necessary body of knowledge. The "problem-first" approach in PBL ensures that students know why they are learning about what they are learning (Gallagher et al., 1995), hence rising intrinsic motivation for learning (Chin & Chia, 2004).

Literature indicated effectiveness of PBL on development of a range of skills comprising active participation in learning process, taking responsibility for their own learning, becoming better learners in terms of communication and group work skills, evaluating different resources and assessing validity of these resources (Bernstein, Tipping, Bercovitz, & Skinner 1995, Eng, 2000, Gibbon & Wall 2005, Lieux, 1996, Lo, 2004, Vernon, 1995). According to Peterson and Treagust (2001) PBL was defined to develop students' knowledge bases in their profession, and their reasoning and problem-solving abilities related with the discipline. Additionally, PBL helped students improve their critical thinking, problem solving and time management skills and encouraged them to do research for more detailed information beyond what was presented in the classroom (Araz & Sungur, 2007). As a different perspective, McBroom and McBroom (2001) proposed that students who completed the PBL tasks experienced change in attitude toward PBL application with positive direction and an apparent gain in self-confidence. Similarly, Harland (2002) observed that students in PBL environment undertook both of roles of teacher and student and they contributed to increase in knowledge levels of peers and teachers. Yee (2007) wrote other important advantages of PBL as to provide easier understanding and use of knowledge, positive attitude toward learning, and positive relationship among students and to increase in higher order thinking skills.

In the studies showing the effectiveness of PBL, advantages of PBL were shown from different points of view and its effect on higher order thinking skills were shown to be positive. In the process of PBL, students are in need of use higher order thinking skills while they decide on which of strategies and techniques should be used, which solution ways can be used and how they incorporate selected solution into application plan (Bentley and Watts, 1989). Higher order thinking skills correspond to analysis, synthesis and evaluation stages of Bloom's taxonomy of cognitive abilities. Indeed, learning experiences focusing on analysis, evaluation, and synthesis, develop skills in problem solving, inferring, estimating, predicting, generalising and creative thinking, question

posing, decision making, critical and systemic thinking, which are all considered as higher order thinking skills (Dori et al, 2003, Barak et al., 2007). In addition to these, reasoning ability is another type of higher order thinking skills as a potential variable for PBL studies. Piagetian approach accepts reasoning ability as higher level cognitive ability and the most important indicator of cognitive development. Differently from other higher order thinking skills, reasoning ability is an important ingredient of inquiry process and informed decision making . Prominence of inquiry and informed decision making have been indicated by different studies in science education literature (Abd-El-Khalick et al., 2004; Chin & Chia, 2006). Reasoning ability has also an important role in meaningfully construction of science concepts (Tan, 2007, Lawson et al.,2007). By taking into account importance and potential of reasoning ability for inquiry process, informed decision making and academic performances of students, this study focused effect of PBL as acontext for inquiry process on reasoning ability as a dependent variable indicating higher order thinking skill.

As another point, majority of existent literature on PBL at the level of elementary education have not used facilitators such as computer simulations (Araz & Sungur, 2007). But, simulations have a great potential for PBL teaching process. According to Sahin (2006), instruction supported by computer simulations provides students the opportunity to observe a real world experience and interact with it. Especially, in science classrooms, simulation can play an important role in creating virtual experiments and inquiry. At the same time, simulations might contribute to conceptual change, provide open-ended experiences for students; provide tools for scientific inquiry and problem solving experiences. In line with these ideas, Araz and Sungur (2007) also recommended use of simulation to increase effectiveness of PBL and stated that computer simulations facilitate to learn concepts and processes of science by PBL.

Therefore, the purpose ofthis study is to investigate effectiveness of PBL application supported by interactive computer simulations on reasoning ability.

2. Method

The study was conducted with a quantitative methodology by using a non-equivalent groups quasi-experimental design. For purpose ofthe study, PBL applications were conducted in two intact classes ofan elementary school in Zonguldak, Turkey.

2.1. Sample

The sample ofthis research consisted of 54 students (28-experimental group, 26-control group ) enrolled in two eighth grade classes of a public middle school in Zonguldak, Turkey. The mean age ofthe students was 14 and majority ofthe students were from middle-class families in terms of socio-economical status. One ofthe classes was randomly assigned as experimental group and instructed by means of PBL, whereas the other class was assigned as the control group and instructed by means of common instructional approach. The applications made in both groups were done by teacher ofthe classes.

2.2. Instruments

In this study, in addition to personal information questionnaire, one instrument; The Test of Logical Thinking was utilized to collect data. The instrument was applied as pre and post-tests in both groups.

2.2.1. The Test of Logical Thinking (TOLT)

The Test of Logical Thinking (TOLT) developed by Roadrangka, Yeany and Padilla (1982) and adapted by Korkmaz (2002) was used to measure formal reasoning ability ofthe students. The test included 18 multiple choice and three open ended items. Students respond to each item by selecting a response and also their reason

for selecting that response. For an item to be scored correct, the student must give both the best answer and the best justification. TOLT measured 6 logical processes. These processes are conservation (litem), mass (1 item), length (1 item), volume (1 item), proportional comparison (6 item), controlling the variables (4 item), consolidative comparison (3 item), probabilistic comparison (2 item) and relational comparison (2 item). According to the study of Korkmaz (2002), the test was found to be appropriate for students at 6th grade level and above. The time required for completion of the test was 45 minutes The alpha reliability of the test was 0.77. In the scoring process, one point was given to each true answer and satisfactory reason for the first 18 items, and one point was given to each true answer for the other questions.

2.3 Treatment

A total of 54 eighth grade students enrolled in science courses a middle school were involved in the study. The study was carried out during four weeks in 2009-2010 fall semester (total number of hours for unit =16 hours). The instruction period for each class was four 40-minute sessions per week.

Experimental group, in which PBL was applied, included heterogeneous groups of four or five individuals who varied in gender and academic achievement. To construct heterogeneous groups was thought to be effective in providing high level interaction among students (Watson & Marshall, 1995). After construction of the heterogeneous groups and pretesting, each of the groups in experimental group was asked to produce problem situations regarding to one of the titles about "buoyant force in liquids and gases and related factors" subject at the first stage of the study. Then, the groups constructed scenarios including at least three alternatives ofproblem sentences after they wrote problem questions. In the following stage, the groups chose one scenario from three alternatives by discussing about the aspects of the scenarios. After the selection of scenario, the groups determined three sub-problems about their scenarios. Then, members of the groups presented their prior knowledge about scenario and its sub-problems. In addition, the participants decided about what they needed to know further and they shared task about researching on the scenario and the sub-problems by using reliable knowledge resources.

In the second stage, the groups evaluated and synthesized knowledge they found in the different sources; internet, journals, and books etc. Moreover, the participants used interactive computer simulations and packet programs about the subject in school computer lab. Based on their knowledge, the groups suggested different solutions on each sub-problem by brainstorming. By the way of brainstorming, the groups recommended too many solution ways as possible as they have done. After finding solution ways, the groups decided about which solution ways were valid and reliable. For making decisions, the groups shared the task of reaching experts and finding additional resources.

In the third stage, the groups eliminated some of alternative solution ways by using expert opinion and knowledge from resources and explained the most appropriate solution way for each sub-problem by stating the rationale of the eliminations. Then, the groups wrote their solution ways for each sub-problem in the form of hypothesis. The reason for asking to write the solution ways in form of hypothesis was that students should design experiments to test these hypotheses. As such, the groups might also have taken the opportunity of presenting their solution ways in an order. For the following stage, each group also shared the task of finding required materials and tools regarding to their experiments.

In the fourth stage, the groups designed their experiments and tested the hypotheses in an order. First, the groups made trials on their experiments before presenting them. Second, they presented their experiments to whole class. Therefore, the experiments were observed by the other groups of the same class. At the last stage, the instrument was applied as post-test.

During the process of applications made by the students, teacher observed all groups by visiting them and provided guidance when it was required. Teacher did not give any content knowledge in spite of the groups' demands for driving the groups to do more research by themselves. At the same time, teacher examined all of the works of the groups and provided feedback for lack parts. In some situations, teacher warned the groups for studying as a group rather than individual struggles and recalled importance of group performance. In addition,

teacher facilitated the process of applications by providing support for the great problems which had a potential to interfere with the process ofthe study.

In the control group, traditional method was used during the study time. The learning environment was teacher-centered and lessons were taught by considering objectives ofthe units with lecture and question-answer techniques. The units were the same with those for experimental group. The students were asked to be prepared for the units before the lessons and question-answer technique was used as beginning activity to teach the unit. Pre-knowledge levels of them were determined and the studies on the unit were presented with lecture and question-answer approaches. After that activity, the students were asked to study on the subjects. The control group students experienced an instruction in which explanations and questions of the teacher were focus and knowledge-centered approach was conducted. In this process, the direction of communication between student and teacher was from teacher to students. Similarly to experimental group students, control group students took the instrument as pre-and post tests.

2.4. Data Analysis

In the study, two variables; one dependent and one independent, were investigated. For analyzing ofthe data, t tests for independent and paired samples were utilized for its appropriateness to compare two groups on dependent variable. For purpose ofthis study, four different statistical processes were conducted, so family-wise alpha level (.05) was adjusted by Benforroni approach. Therefore, throughout analyses, .0125 was used as alpha value in this study.

3. Results

To compare the students' pre and post test scores of reasoning, the TOLT was administered to both groups before and after the treatment. In order to examine the effectiveness ofthe PBL on students' reasoning abilities, the scores acquired in pre- and post-tests ofthe TOLT were analysed by t-tests.

As can be seen in Table 1, independent sample t-test analysis showed no statistically significant difference between the mean scores ofthe control and experimental groups with respect to their prior reasoning abilities on the TOLT (Mco„t = 3.53; SDco„t = 2.25 and Mexp = 4.46; SDexp = 3.32; t<52)= .23 3; p>.0125). The magnitude ofthe

difference in the means was small (^ =.02) This result demonstrated that the students' reasoning ability levels

in both groups were similar to each other before the treatment.

When looked at the results after the treatment, independent sample t-test analysis revealed a statistically significant difference between the control and experimental groups' mean scores on the TOLT in favour of the experimental group (Mco„t = 3.75; SDco„t = 2.60 and Mexp = 6.00; SDexp = 3.45; t<52) = 2.71; p<.0125). The

magnitude of the differences in the means was medium (^ =.12. ^The students in the experimental group demonstrated more increase in reasoning ability than the control group students.

Table 1 Independent t-test results for groups' reasonimg ability scores

Tests Groups N M SD df t P l1

Pre-test Control group 28 3.53 2.25 52 1.2 .233 0.02

Experimental group 26 4.46 3.32

Post-test Control group 28 3.75 2.60 52 2.71 .009* 0.12

Experimental group 26 6.00 3.45

Paired sample t-test statistics showed a no statistically significant mean difference between pre- and post-test mean scores of control group (M = 3.75; SD = 2.60; t(27) = .62; p>.0125, Eta squared" 01) while there was a statistically significant mean difference between pre- and post-test mean scores of experimental group (M = 6.00; SD = 3.45; t(25) = 2.79; p<.0125, Eta squared=.24) with respect to reasoning ability on the TOLT (Table 2).

Table 2. Paired t-test results for groups' reasoning ability scores

Groups Tests N M SD df t P

Control group Pre-test 28 3.53 2.25 27 .62 .53 0.01

Post-test 28 3.75 2.60

Experimental group Pre-test 26 4.46 3.32 25 2.79 .01* 0.24

Post-test 26 6.00 3.45

4. Discussion

This study compared effectiveness of PBL instruction supported by computer simulations and common instructional approach on elementary students' reasoning ability at the context of "Buoyant Force in liquids and gases" subject. The results of this study showed that the students in PBL group had higher reasoning ability than the students in comparison group after the treatment. The difference between groups can be explained by effectiveness of PBL process on reasoning ability components. The TOLT included items on proportional comparison, controlling variables, consolidative comparison, probabilistic comparison and relational comparison as components of reasoning ability. In parallel to the components of the test, PBL application might have provided the opportunity of using higher-order reasoning components in finding useful solution ways. In addition, the students might have taken the opportunity to use reasoning ability during the first two stages of PBL application in which the students gathered knowledge, commented on the knowledge and eventually synthesized what they have learned. Studies have also shown that by reflecting upon learning during PBL process, students are able to analyse and synthesize the contextual information, acquire further knowledge and assimilate it into their existing knowledge base (Nelson, Sadler, & Surtees, 2004). According to Lam (2009) many studies have found that students in PBL curricula are likely to transfer higher order thinking to new situations. The study carried out by Krynock and Robb (1996) showed that PBL does increase higher order thinking skills of eight grade students by requiring them to think about a problem critically and analyzing data to find the solution. Wong and Day (2009) have also found PBL to be effective on increasing higher-order thinking ability at the level of

junior secondary school. These results are in line with result of this study on higher order thinking skills as correlates ofreasoning ability.

In the world, what is important for people who need solve open-ended problems in collaboration for their life is to use knowledge effectively rather than to record simply knowledge into mind. With this idea in mind, requirement for PBL applications in learning contexts emerges due to focus ofthe approach on group processes, problem solving and real life situations. Every effort in dealing with ill-structured open-ended problems by studying in groups might lead to departure with maximum gains from learning environments. PBL applications might provide much more benefits from use of knowledge for solution to gain of higher order thinking skills (e.g. reasoning ability, creative thinking, critical thinking etc.) and of collaborative study habits such as communication and interaction than traditional applications. PBL might be used more effectively in learning contexts. For instance; technologically equipped PBL contexts might be used to increase visuality ofthe subject. Again, if this way is accompanied by interactive experience, the students can focus on the problem more effectively and internalize the problem.

In this study, effectiveness of PBL on reasoning ability has been shown. In the effectiveness ofthe approach, incorporation of the computer simulation was thought to be contributor and facilitator. For the role of computer simulations, it can be said that abstract concepts and principles might be converted into more concrete subjects by the simulations. The same effect ofthe simulation might have been valid for the increase in reasoning ability. As stated by Sahin (2006), simulations can contribute to conceptual change, provide open-ended experiences for students; provide tools for scientific inquiry and problem solving experiences. In addition, Kumar and Sherwood (2007) have shown the effectiveness of problem based simulations on conceptual understandings of students. In another study of Kumar (2010), he stated that interactive video technology reached new heights in providing anchors for problem-based learning. During inquiry process supported with visualisation, development of reasoning ability is easier due to continuous use ofreasoning ability in inquiry process.

The results of this study have importance in science education. First, the study has been providing empirical evidence for effectiveness of PBL supported with computer simulations at the level of elementary students. Second, the experimental nature ofthe study has been giving the opportunity of finding cause-effect relationship. As the other implication ofthis study, applications ofthe study have been providing a guide for science educators who want to desing an instruction by using PBL approach to increase reasoning ability. The support of the computer simulations is another important aspect of this study, because the abstract concepts of physics have been converted into more concrete objects. Therefore, this study has been describing a way of incorporation of effective computer simulations into PBL instruction.

Although the study has an importance for application of PBL in science education environment, this study has some limitations regarding to internal and external validity. Number of the subjects and the topic studied are limitations of this study for generazilibility aspect. In addition, quasi-experimental nature of the study with non-random assingment is another limitation to eliminate threat factor including pre-existent difference between participant characteristics ofthe groups.

Based on the results ofthis study, it can be suggested that more sample is needed to increase generalizability ofthe study. At the same time, the subject of "buoyant force in liquids and gases" has been focused in this study, so the method should be applied to other physics subjects to increase external vailidity ofthe study. As another suggestion, true experimental method should be used with random assignment in future studies to overcome internal validity threats.


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Appendix A. Examples of Simulations

Screen 1.

The student doesn't observe any changes until he interacts with the simulation. When the "release" button on the simulation is pressed, both objects tied to the two dynamometers are released. As one ofthe objects drops into the liquid in the beaker glass, the other remains in the same atmosphere (in the air). As buoyant force is applied to the object in the liquid, the value read on the dynamometer decreases considerably.

Screen 2.

The objects inside the glass globe and in the atmospheric environment which are tied to dynamometers are released when the "release" button is pushed. In addition, in order to empty the air in the glass globe, the amount of air inside the glass globe is adjusted by clicking the arrows near the cylinder. When the arrow which points to

the right is clicked, the cylinder comes out and the air inside the globe is emptied. If it is emptied (on condition that the cylinder is already out) as the arrow which points to the left is clicked, the cyliner goes in and the globe is filled with air. The air in the globe can be checke via the gauge connected to the globe. Ifthe user has emptied the air inside the globe with the help of the cylinder, when released, the objects are balanced in a state in which the object inside the globe is lower. Ifthe air inside the globe hasn't been emptied, both obects are balanced at the same level.

Screen 3.

In the section where the variables which buoyant force is dependent on except gravitational acceleration are analysed, the user can adjust the mass and volume of the object and the density of the liquid as desired.The density of the object is not displayed until the mass and volume of the object take a numeric value. The information as to how the user is going to change these variables is represented by the balloon which appears when the user puts the cursor on the names of sliders. Similarly, the value of the buoyant force appears on the screen when the density of the liquid is adjusted. The simulation doesn't make any calculations until the user defines values for all the variables. When all the variables on which buoyant force have been defined, the value of the buoyant force is presented by the simulation. When any change on the variables is made, the oject immersed into the liquid is affected by these changes, and the location of the object is updated according to the interaction between, the density of the object and that of the liquid. This update process is animated in the animation and the onject moves in a way close to real. Numeric values are provided on the panel about the immersed part of the object. To get information about the location of the object, the pointer is moved on the object, information about the location is provided in the speech balloon that appears on the screen. When the help icon on the table is clicked, a help screen about the simulation appears.