Research: Science and Education edited by
Chemical Education Research
Diane M. Bunce The Catholic University of America Washington, DC 20064
Effects of a Cooperative Learning Strategy on Teaching and Learning Phases of Matter and One-Component Phase Diagrams
Melanie M. Cooper Clemson University Clemson, SC 29634-1905
W
Kemal Doymus Kazim Karabekir Education Faculty, Department of Elementary Science Education, Ataturk University, 25240 Erzurum, Turkey;
[email protected] In chemistry education, most teachers in primary, secondary, and college institutions use traditional pedagogical methods in which students are passive listeners. Some teachers use methods in which students are more actively participating through writing. However, cooperative learning methods enable students to express their individual thoughts freely and to discuss their ideas and to listen to each other. Well-designed cooperative learning also enables more effective, productive, and quick teaching and learning activities (1). Cooperative learning helps students to speak effectively in group discussions. Additionally, this method gives information to students about study techniques like questioning and answering, free discussions, small- and large-group discussions, circle discussions, seminars, and brainstorming (2–5). Research has indicated that cooperative learning has positive effects at the elementary (6, 7), secondary (8, 9) and college level (10, 11). Furthermore, Slavin (12) notes that most studies have focused on the effects of cooperative learning in grades 2–9. Cooperative learning methods are thought to have the greatest potential to promote cognitive and noncognitive skills (13). Research reports that these methods encourage the development of a more supportive social atmosphere within the classroom, more independent work, improvements in communication, cooperation skills, and self-esteem (14). Nevertheless, these methods are rarely applied in science classes in Turkey (1). Cooperative learning is a comprehensive approach to teaching that derives from a theory of education encompassing key assumptions about what and how students should learn. Lessons taught with cooperative learning strategies are arranged so that each student, ranging from the fastest to the slowest learner, makes a contribution to learning (15). Many cooperative learning methods make use of the principles of cooperative learning for specific purposes. Currently, the most widely used cooperative learning methods include: student Teams-Achievement Divisions and Teams-Games-Tournament (16), Learning Together (17), Group-Investigation (18), and Jigsaw (19). Jigsaw is an important method of cooperative learning originally designed by Elliot Aronson and his colleagues at the University of Texas and the University of California at Santa Cruz. Students are assigned different academic materials, which they then teach to the team (20). In this method, students are members of two different groups, the “home group” and the “jigsaw group”. Initially, students meet in their home groups, and each member of the home group is assigned a portion of the material to learn as an “expert” (20, www.JCE.DivCHED.org
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21). The home groups then break apart, like pieces of a jigsaw puzzle, and students move into jigsaw groups consisting of members from the other home groups who have been assigned to the same portion of the material. While in the jigsaw groups, the students discuss their assigned material to ensure that they understand it. Students then return to their home groups, where they teach their material to the rest of their group (9, 22–25). In this study, students learned about phases of matter and one-component phase diagrams in a class environment where the jigsaw method of cooperative learning was used for teaching and learning. Students’ comprehension of the material was subsequently evaluated via grade achievement. Method The subjects of the present study comprised 108 university students who were enrolled in two classes of the general chemistry course during the 2004–2005 academic year. The data were obtained from 52 students in the experimental group using jigsaw cooperative learning methods, and 56 students in the control group taught by traditional methods. Instruments The primary goal of this study was to investigate the effectiveness of cooperative learning methods compared with traditional methods of instruction on students’ academic achievement in the general chemistry course. The Chemistry Achievement Test (CAT) and Phase Achievement Test (PAT) were used. The questions used on the PAT are available as Supplemental Material.W The CAT consists of 20 multiplechoice questions. The questions in the test (26) were related to solids, liquids, gases, bonding, matter, and matter states. This test was given to students who were not involved in the study but had previously taken the course in which the phase of matter topics mentioned above had been taught. The reliability coefficient of this test (CAT) was 0.79. The PAT, developed by the author and three chemistry teachers, was divided into four modules. Each module consisted of four multiple-choice questions (see the Supplemental MaterialW). Each module of the test was written by four teachers and reviewed by the other teachers of the chemistry course. Each module was then applied to three classes of high school chemistry students who were not involved in this study. Item analyses were calculated for each question, and
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confusing or vague questions were rewritten before the test was used in the study. The KR-20 values for each of the four module achievement tests are provided in Table 1. Table 1. Comparative Reliability Measures for Tests on Phase of Matter Topics Test
Phase Topics Tested
N Values
KR-20 Values
Module I
Solid–Liquid
52
0.72
Module II
Solid–Gas
52
0.58
Module III
Liquid–Gas
52
0.72
Module IV
Triple-Point Equilibrium
52
0.72
PAT
All
52
0.71
Figure 1. Phase diagram of data charted from the home groups of the experimental group, which used jigsaw cooperative learning methods. (S1, …S6; L1, …L6 and G1, …G6 indicate the students in the group.)
Figure 2. Phase diagram of data charted from the combined jigsaw groupings of the experimental group, which used cooperative learning methods.
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The Cooperative Teaching and Learning Process
Determining Experimental and Control Classes In both groups, this study was conducted over a threeweek period during which phase and one-component phase diagrams were taught as part of the regular curriculum in the general chemistry course. Classroom instruction for both groups consisted of four class hours per week. A total of 108 students from two classes were involved in the study. One of the classes was treated as the experimental group and other class was used as the study’s control group. To examine the effect of the treatment on academic achievement, and to determine the students’ previous learning in chemistry, the CAT was administered to both groups as a pre-test before treatment. Next, phase and one-component phase diagrams were studied in both groups. Two different instructors were involved in the teaching. While one of the teachers (the researcher), actually taught the course, the second teacher, an expert in physical chemistry, observed the teaching process in both the jigsaw group and control group. Forming and Re-Forming Jigsaw Groups As indicated in Figure 1, the students in the experimental group were divided into three home groups representing each of the three phases of matter (solid, liquid, and gas). In this instance, each home group contained six students, however the number of home groups in a class can be increased or decreased so that every student in the class can participate in the jigsaw method. Student groups were formed randomly by the instructor. The students in the Solid Group (SG) learned and prepared to teach about characteristics of solids, types of solids, solid cells, and crystal structures, and then presented these subjects to the whole class. The students in the Liquid Group (LG) likewise learned, prepared, and presented topics on the characteristics of liquids, types of chemical bonds, boiling points, surface tension, and viscosity. The Gas Group (GG) learned, prepared, and presented the following topics to the whole class: characteristics of gases, partial pressure, gas laws, and ideal and real gases. After the presentations of the solid, liquid, and gas phases in the one-component phase diagram, students in the three home groups formed new groups (Figure 2). The composition of the new Solid–Liquid Group (SLG) was created by moving two students from the SG and two students from the LG. Likewise the Solid–Gas Group (SGG) was formed by moving two students from the SG and two from the GG. Lastly, the Liquid–Gas Group (LGG) was formed by moving two students from the LG and two from the GG. Following this, a fourth group, the Triple-Point Group (TPG), was formed from the remaining two students in each main group (SG, LG, and GG). Students in the newly formed SLG prepared and presented material on melting and freezing—liquid and solid equilibrium—to the class. The SGG students prepared and presented material on sublimation and deposition—equilibrium formed between solid and gas—to the class. The LGG students prepared and presented material on evaporation and condensation—equilibrium pressure and heat where liquid and gas were together. The TPG students prepared material
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Research: Science and Education
on equilibrium pressure and heat in which solid, liquid, and gas exist. The students in the SGG, LGG, SLG, and TPG met with each other in the classroom: each group presented their topics to the class for 20 minutes and then discussed related topics for 20 minutes. Following these presentations of topics and one-component phase diagrams, experimental and control group students took both the CAT and PAT as a post-test. The data obtained were evaluated using SPSS (http://www.spss.com/ [accessed Jul 2007]). Responses from students who did not answer all the CAT and PAT questions were not included in the evaluation.
experience of undergraduate chemistry students. The results obtained from this study concur with prior studies reported by Tomblin and Davis (34) and Okebukola (35). The use of phase diagrams and other simple physical constructs could add an intellectually stimulating and meaningful dimension to a discussion of many of the descriptive aspects of general chemistry. By including in these discussions the importance of pressure and its influence on structure and properties, students can gain an appreciation of the concept of equilibrium even before it is formally addressed in phase and phase diagram chemistry, and solid, liquid, and
Findings and Discussion Prior to treatment, an independent t-test was employed to determine whether a statistically significant mean difference existed between the control and experimental groups with respect to chemistry achievement measured by CAT. No statistically significant mean difference was found between the two groups before treatment (t ⫽ 0.86, p ⫽ 0.389) (see Table 2). Then an independent t-test was carried out to compare the effect of the type of instruction on students’ chemistry achievement measured by CAT as a post-test after treatment. The data indicated that there was a significant difference in chemistry achievement between the experimental group and the control group (t ⫽ 4.47, p ⫽ 0.001 (see Table 3). Students in the experimental group scored significantly higher than those in the control group after the instruction. As shown in Table 3, the PAT was administered at the end of four weeks in both the experimental and control group students after the instruction. The results of the PAT given in Table 2 clearly show that a significant difference exists between the mean scores of the experimental and control groups with respect to the questions in Module I (t ⫽ 3.323; p < 0.05), Module II (t ⫽ 4.725; p < 0.05), Module III (t ⫽ 7.205; p < 0.05) and Module IV (t ⫽ 4.505; p < 0.05). Considering the mean score in Table 3, it is clear that the mean score of the experimental group was higher than that of the control group in Modules I–IV. The mean scores of the experimental and control groups were higher for Module I (solid–liquid) and Module III (liquid–gas) when compared to those for Module II (solid–gas) and Module IV (triple-point equilibrium). In a study of one-component phase diagrams (27, 28), students learned the equilibrium of solid–liquid and liquid–gas. However, in the present study, the mean score of either the experimental or the control group decreased for Module II (solid–gas) and Module IV (triplepoint equilibrium) (see Table 3). The reason for the decrease in score was that the students had difficulties in comprehending the equilibrium of solid–liquid–gas at the triple point of the phase diagram (29, 30).
Table 2. Comparative t-Test Analyses of Pre- and Post-Test CAT Scores
Pre-Test
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Post-Test
SD Values
t-Test Values
p Values
Experimental (40)
18.07
3.213
0.860
0.389
Control (48)
17.50
3.215
Experimental (40)
21.50
2.400
4.478
0.001
Control (48)
18.80
3.080
Post-Test a
Maximum score for these tests was 30 points.
Table 3. Comparative t-Test Analyses of PAT Modules’ Test Scores Test Modules
Group (N)
Meana Values
SD Values
t-Test Values
p Values
I
Experimental (46)
96.52
8.75
3.323
0.001
Control (54)
85.93
20.05
Experimental (46)
88.20
13.71
4.725
0.001
Control (54)
69.63
23.55
Experimental (46)
93.04
11.33
7.205
0.001
Control (54)
72.59
16.16
Experimental (46)
63.04
8.400
4.505
0.001
Control (54)
54.81
9.660
II
III
IV
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Meana Values
Pre-Test
Conclusions and Recommendations In most prior studies, jigsaw cooperative teaching and learning methods were found to be no more effective in terms of academic achievement than the traditional (control group) comparison treatments (31–33). In our study, jigsaw had a significant positive effect on the phase diagram learning
Group (N)
Instrument Used
a
Maximum score for these tests was 100 points.
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gas equilibria. Likewise, a discussion of phase diagrams containing slightly more detail provides a useful point of departure during later discussions of equilibrium topics, particularly thermodynamics (28). When provided with a phase diagram, the product of fundamental theoretical and experimental research, and a discussion of its physical and chemical relevance, students could begin to make the connection between the chemistry of atoms and molecules on the one hand, and the natural world around them on the other. This is indeed one of the most important aims of the general chemistry course. W
Supplemental Material
The questions used on the Phase Achievement Test are available in this issue of JCE Online. Literature Cited 1. Doymus, K.; Simsek, U.; Bayrakceken, S. Turkish J. Sci. Educ. 2004, 2, 103–113. 2. Bolling, A. J. Excell. Coll. Teach. 1994, 5, 47–55. 3. Gardener, B. S.; Korth, S. D. J. Excell. Coll. Teach. 1996, 7, 17– 30. 4. Cooney, M.; Nelson, J.; Williams, K. J. Excell. Coll. Teach. 1998, 9, 65–79. 5. Johnson, D. W.; Marumay, G.; Johnson, R. T.; Nelson, D.; Skon, L. Psychological Bulletin 1981, 94, 429–445. 6. Slavin, R.; Leavey, M. B.; Madden, N. A. The Elementary School Journal 1984, 84, 409–422. 7. Johnson, D.; Johnson, R.; Scott, L. J. Social Psychol. 1978, 104, 207–216. 8. Lazarowitz, R.; Hertz, R. L.; Baird, J. H. Sci. Educ. 1988, 2, 475–487. 9. Eilks, I. J. Chem. Educ. 2005, 82, 313–319. 10. Levine, E. J. Excell. Coll. Teach. 2001, 31, 122–125. 11. Bowen, C. W. J. Chem. Educ. 2000, 77, 116–119. 12. Slavin, R. Educ. Leader. 1989, 47, 52 –54. 13. Johnson, D. W.; Johnson, R. T. In Applied Social Psychology Annual 4; Brickman, L., Ed.; Sage Publishing Company: Beverly Hills, CA, 1983; p 119. 14. Tingie, J. B.; Good, R. J. Res. Sci. Teach. 1990, 27, 671.
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15. Samuel, W. W.; John, G. M. Int. Educ. J. 2004, 5, 26–36. 16. Slavin, R. E. Rev. Educ. Res. 1980, 50, 315–342. 17. Johnson, D. W.; Johnson, R. T. Learning Together and Alone, 2nd ed.; Allyn & Bacon: Boston, 1994. 18. Sharan, S.; Hertz-Lazarowitz, R. A Group Investigation Method of Cooperative Learning in the Classroom. In Cooperation in Education: Based on the Proceedings of the First International Conference on Cooperation in Education, Tel Aviv, Israel, July, 1979, Sharan, S., Hare, A. P., Webb, C., Hertz-Lazarowitz, R., Eds.; Brigham Young University Press: Provo, UT, 1980; pp 19–46. 19. Aronson, E. The Jigsaw Classroom; Sage Publications: Beverly Hills, CA, 1978. 20. Gilbert, A. L. J. Agricul. Educ. 1989, 2, 1–9. 21. Slavin, R. E. Cooperative Learning Theory, Research and Practice, 2nd ed.; Allyn & Bacon: Boston, 1995. 22. Colosi, J. C.; Zales, C. R. Bioscience 1998, 48, 118–124. 23. Choe, S. T. W.; Drennan, P. M. J. Coll. Sci. Teach. 2001, 30, 328–330. 24. Mantingly, R. M.; VanSickle, R. L. Soc. Educ. 1991, 55, 392– 395. 25. Seetharam, M.; Musier-Forsyth, K. J. Chem. Educ. 2003, 80, 1404–1407. 26. ConcepTests for General Chemistry, as used by Judith Herzfeld at Brandeis University. http://people.brandeis.edu/~herzfeld/ alphabetical.html (accessed Jul 2007). 27. Glasser, L. J. Chem. Educ. 2002, 79, 874–876. 28. Gramsch, S. A. J. Chem. Educ. 2000, 77, 718–722. 29. Gavin, D. P.; McNaught, I. J. J. Chem. Educ. 1993, 70, 560– 561. 30. Glasser, L. J. Chem. Educ. 2004, 81, 414–418. 31. Hertz-Lazamwitz, R.; Carmela, S.; Shlomo. S. Academic and Social Effects of Two Cooperative Learning Methods in Desegregated Classrooms; Haifa University: Haifa, Israel, 1981. 32. Moskowitz, J. M.; Malvin, J. H.; Schaeffer, G. A.; Schaps, E. Am. Educ. Res. J. 1983, 20, 687–696. 33. Palmer, J.; Johnson, J. T. l. Soc. Stud. Res. 1989, 13, 34–39. 34. Tomblin, E. A.; Davis, B. R. A Study of Cooperative Learning Environments; San Diego Public Schools: San Diego, California, 1985. 35. Okebukola, P. A. Sci. Educ. 1985, 69, 501–509.
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