Investigating the Impact of Adding an Environmental Focus to a

Research: Science and Education edited by

Diane M. Bunce The Catholic University of America Washington, DC 20064

Investigating the Impact of Adding an Environmental Focus to a Developmental Chemistry Course

Ren ee S. Cole University of Central Missouri Warrensburg, MO 64093

Beth Robelia* Kitchen Table Learning, Saint Paul, Minnesota 55108 *[email protected] Kristopher McNeill ETH Zurich, Department of Environmental Sciences, Zurich, Switzerland Kristine Wammer Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105-1079 Frances Lawrenz Department of Educational Psychology, University of Minnesota, Minneapolis, Minnesota 55455

Chemistry educators have long sought to make chemistry relevant by using examples that chemistry students encounter in their everyday lives. However, little quantitative research explores how including relevant examples impacts student learning of chemistry content or what types of applications of chemistry are the most useful in developing understanding. The college curriculum Chemistry Modules (1), which uses context to teach chemistry concepts as they are needed to understand the context, has one experimental study that indicates students who use this curriculum are more successful in learning certain aspects of content and science process than their peers in conventional classes (2). Research on Chemistry in Context (3), another college curriculum, shows students' attitudes about chemistry improved across a semester (4). Two high school curricula that use everyday contexts to make content more appealing to students have some research to support them. Chemistry in the Community ( ChemCom), a curriculum designed by the American Chemical Society (5), has one experimental study showing that students using the ChemCom curriculum did better on chemistry posttests than their peers in a more conventional course (6). Salters Advanced Chemistry (7), a curriculum used in the United Kingdom, is somewhat similar to ChemCom. Few studies document what students do learn in the Salters curriculum (8, 9); one study showed little difference between what students learned using the Salters approach and what students learned in a more conventional curriculum (10). Although little experimental research exists, both curricula continue to be used by high school teachers who provide ample anecdotal evidence that their students enjoy learning chemistry more when it is put into more familiar contexts (11, 12). Chemistry Modules, ChemCom, and Salters include environmental examples. A five-year evaluation report on ChemCom published in this Journal in 1992 stated that students wanted to learn chemistry through environmental contexts (11). None of these curricula separates types of examples, nor does any research 216

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investigate which contexts are most effective in teaching particular chemical concepts. The authors of this study intended to frame a majority of the content for a developmental chemistry course in an environmental context, hypothesizing that environmental topics would spur students toward learning more chemistry and changing their attitudes to become more proenvironmental. Others have organized developmental courses around environmental topics, although their studies do not contain objective, quantitative measures of student achievement. Swan and Spiro (13) reported on a course for nonmajors developed under a National Science Foundation grant. The course From Ozone to Oil Spills successfully integrated a number of environmental contexts to introduce basic chemistry concepts. In the first semester of the course, the environmental issues were only introduced after the chemistry, about 45 min into the lecture. The instructors found more success the second semester when they introduced an environmental issue at the beginning of lecture with relevant chemistry concepts to follow. One of the lectures began by polling students whether paper or polystyrene cups were better for the environment. Polymer chemistry was introduced with repeated references to the paper and polystyrene cups example to illustrate chemical concepts as they arose. The present study used a similar technique. Swan and Spiro (13) did not report any quantitative results on their course, nor were any efforts made to methodically compare the outcomes of their course to more conventional courses. Denise Battles and her colleagues at Georgia Southern University also reported successfully integrating environmental topics into four undergraduate science courses for nonmajors, including chemistry. Battles et al. (14) provide student selfreports of how much the course improved the students' understanding of environmental issues, but this study does not provide objective, quantitative information on student achievement. Women and African-American students were the most positive about how the course affected their learning. Both Battles'

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Vol. 87 No. 2 February 2010 pubs.acs.org/jchemeduc r 2010 American Chemical Society and Division of Chemical Education, Inc. 10.1021/ed800056e Published on Web 01/12/2010

Research: Science and Education

courses and the environmental chemistry course Swan and Spiro described answer Uri Zoller's call for inclusion of more environmental chemistry in introductory courses (15). The present study also incorporates some of Zoller's sweeping recommendations for more emphasis on environmental responsibility in chemistry courses, including environmental topics in an introductory course and using case studies to illustrate environmental problems. Study Overview Two sections of developmental chemistry at a large midwestern university were cotaught by two instructors, such that one instructor taught both sections the first week and the other instructor taught both sections the following week. The instructors continued to alternate for the entire semester. The dual instructor design was intended to ensure any differences that appeared in the assessment results for each course were not because of differences in instructors. The course was a one-semester general chemistry overview course taught at a lower level than the standard two-semester general chemistry sequence. Both sections were evening lecture courses that included one 150-min lecture period and an associated 150-min lab period. Both instructors were familiar with environmental chemistry as both were involved in research involving aspects of chemistry relevant to water quality. Quantitative achievement data were collected from both sections at the beginning and end of the semester. Students were also surveyed at the beginning and end of the course about their environmental attitudes, behaviors, and knowledge about environmental myths. Approximately 200 students were enrolled in each section at the beginning of the course. Because of a department policy that prevents individual instructors from changing the content of the laboratory, the laboratory portion of the course was not well integrated with the lecture portion. A single staff member, who is not one of the course lecturers, supervises all of the laboratory sections for the course at this institution. The laboratory curriculum includes conventional introductory chemistry experiments on topics such as density of liquids and solids, determining empirical formulas, and acid-base titrations. It is noteworthy that none of the laboratory experiments included significant environmental content. Treatment Both sections of the developmental chemistry course used real-life examples to illustrate chemical principles. One section used real-life examples connected with environmental issues (treatment section), while the other section focused on real-life examples related to current and historical events (comparison section). In the initial weeks of the course, a problem or situation was presented at the beginning of lecture to frame the chemical content being presented that evening. For example, during the first week of class, information on significant digits was framed by sprinters' times in the Olympics in the comparison section and average temperatures used to track global warming in the treatment section. During the second week of the course, the content was focused on classifying matter and physical and chemical changes. A basic model of the carbon cycle was used to introduce the content in the comparison section. A more complex model of the carbon cycle that included gigatons of carbon moving through

r 2010 American Chemical Society and Division of Chemical Education, Inc.

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the system was used to introduce the content in the treatment section. The more complex model used in the treatment section also included the imbalance of carbon in the atmosphere with statistics about how much carbon dioxide is produced by residents of the United States. For 9 out of the 15 weeks of the semester, separate examples were used to introduce content in the two sections. Other topics included: using the differences in As(III) versus As(V) to solve a crime and an environmental mystery, pH of household substances versus the pH of rain and wastewater, and types of organic compounds present in food versus types of organic compounds in pollution. This method of using context as reciprocity between concepts and applications is congruent with Gilbert's second model in his description of ways context can be used in chemical education (16). For 3 out of the 15 weeks, the examples were the same in each section. The instructor used the lecture time to give midterm exams during an additional 3 weeks. The combination of some lectures using the same examples and some lecture periods being used for exams resulted in a subtle treatment. In addition, the midterm exams did not contain any questions pertaining to the real-life or environmental examples given in class because the instructors wanted to keep exams in both sections of the class very similar; therefore, students may not have perceived the emphasis on putting chemistry in context. Participants Most of the students in each section were typical first-year college students between the ages of 18 and 21. Two-thirds of the students were women, primarily because the developmental course fulfilled the chemistry requirement for prenursing students, who were predominantly female. Other students were enrolled in the course because they did not pass the entrance exam for the regular two-semester sequence of general chemistry. Most of the students in the two sections had taken at least one year of chemistry (presumably in high school) prior to enrolling in the developmental course. Data Collection and Analysis Items on the exams were created by the instructor as well as taken from released versions of standardized exams that were used with permission of the publishers. Reliability values are reported as Cronbach's R, listed after each test. Reliability of a test is an estimate of how a student's scores would correlate if they took a test of equal difficulty on the same subject matter. All students were encouraged to take the 15-item pretest during the first week of the course. The pretest contained items that assessed both general and environmental chemistry knowledge (Cronbach's R = 0.32). Seven general chemistry items assessed concepts such as conservation of mass, nature of covalent bonds, and redox reactions. Eight environmental chemistry items focused on biogeochemical cycles of carbon, nitrogen, phosphorus, and water. The general chemistry items were repeated on the final exam (Cronbach's R = 0.70). The environmental chemistry items were repeated on a 22-item environmental chemistry posttest (Cronbach's R = 0.62) given for extra credit in the course and available as supporting information. Students in both sections also took a 19-item survey at the beginning and end of the course. Students were required to take the survey as part of their course grade but not required to

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Research: Science and Education Table 1. Mean Scores for General Chemistry Assessmentsa Assessment General Chemistry

General Chemistry

General Chemistry

N

Mean (SD) and p Value for Pretest

Comparison

192

3.16 (1.46)

4.47 (1.46)

Treatment

151

2.59 (1.12)

4.50 (1.28)

1.91 (1.72)

p < 0 0.001

p = 0.841

p = 0.003

Females in comparison 128

3.04 (1.53)

4.49 (1.35)

1.43 (2.05)

Females in treatment

2.52 (2.05)

4.51 (1.30)

2.02 (1.62)

p = 0.003

p = 0.90

p = 0.016

46

2.70 (1.15)

4.43 (1.41)

1.74 (1.89)

103

2.52 (1.11)

4.54 (1.23)

2.02 (1.63)

p = 0.391

p = 0.635

p = 0.357

Groups Compared

Males in treatment Females in treatment

a

103

Mean (SD) and p Value for Mean (SD) and p Value for Gain Posttest Scores 1.31 (2.06)

Questions on conservation of mass, nature of covalent bonds, and redox reactions; the maximum score was 7.

provide consent that their responses could be used for research. The survey questions on environmental attitudes, knowledge, and behavior were used with permission from the National Environmental Education and Training Foundation (NEETF) Environmental Report Card of 2001 (17). The survey questions sought student opinions about issues such as air quality, environmental regulations, and choosing between economic and environmental concerns. Survey questions also covered behaviors such as recycling, use of mass transportation, and energy conservation. The NEETF survey was designed to be administered over the phone. In the present study, data were collected via an online course management survey tool. To verify that students were interpreting online NEETF survey questions as expected, 39 student volunteers were interviewed face-to-face using a subset of questions from the NEETF survey. The results of the interviews indicated that the students were interpreting the online survey items in the same way as was intended in the telephone survey; therefore, it was not necessary to include interview results. Research Questions This study was designed to determine whether using an environmental focus would change the amount of general or environmental chemistry students learned in class. The authors hypothesized that students in the treatment section would have higher scores in both general and environmental chemistry. Special attention was paid to women's scores on the assessments and the survey. NEETF surveys have shown that, although women tend to have more pro-environmental attitudes, they tend to have less environmental knowledge (18). The authors wanted to know whether women would respond more favorably to the treatment because of their more pro-environmental attitudes. Researchers have shown that variables other than cognitive ability can predict chemistry achievement, including motivation (19, 20) and approaches to studying (21). It was hypothesized that framing chemistry in an environmental context would impact noncognitive variables. For example, a pro-environmental attitude might translate into more motivation to study chemistry that included environmental examples. In other words, if chemistry became more meaningful for students as a way to understand environmental issues, they might study harder. The authors also hypothesized that students in the treatment section would show greater improvement in their environmental attitudes and behaviors as measured by the NEETF survey. 218


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Results A variety of t-tests were performed to determine whether statistically significant differences in assessment results existed between the treatment and comparison groups. Owing to the number of t-tests on the same assessment data, the significance level (R) was adjusted downward from 0.05 to 0.01 to avoid Type I errors. Gain scores were computed by subtracting students' pretest scores from their posttest scores. General Chemistry As reported in Table 1, significant differences between treatment and comparison groups were found in general chemistry gain scores; however, significant differences were also found in the pretest scores. The treatment group had a lower mean score on the general chemistry pretests, a similar mean on the posttests score, and a higher mean gain score. Another significant difference was found when comparing women's pretest scores from the treatment section to women's scores in the comparison section; the differences in gain scores approached significance at the p < 0.01 level. When men and women in the treatment section were compared with each other, no significant differences were found. Environmental Chemistry Comparing assessment results for environmental chemistry topics between sections revealed no significant differences between sections, between females in the treatment sections compared to females in the comparison section, or for males and females within the treatment section. The numbers in Table 2 represent only students who took both the pretest and posttest. Environmental Survey The responses to the three sections of the NEETF environmental survey were treated separately. The attitude and behavior scores were compiled by adding Likert-scale data, with higher numbers representing more environmentally friendly perspectives and behaviors (see Table 3). For the section that tested knowledge of environmental myths, one point was given for correct answers and incorrect answers received no points. When gain scores for the three sections of the NEETF survey were analyzed using the t-test, attitude gain scores showed a significant difference at the p = 0.05 level. Gain scores were positive for the treatment section and negative for the comparison section.


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Research: Science and Education Table 2. Mean Scores for Environmental Chemistry Assessmentsa Assessment

Nb

Mean (SD) and p Value for Pretest

Mean (SD) and p Value for Posttest

Mean (SD) and p Value for Gain Scores

Comparison

160

2.17 (1.12)

3.26 (1.69)

1.11 (1.82)

Treatment

119

2.01 (1.07)

3.38 (1.63)

1.33 (1.79)

p = 0.257

p = 0.567

p = 0.296

105

2.09 (1.14)

3.31 (1.67)

1.21 (1.82)

78

1.96 (1.11)

3.21 (1.66)

1.23 (1.85)

p = 0.43

p = 0.70

p = 0.94

2.10 (1.00)

3.74 (1.55)

1.61 (1.65)

Groups Compared

Environmental Chemistry


Females in treatment Females in comparison


Males in treatment

39

Females in treatment

78

1.96 (1.11)

3.22 (1.66)

1.23 (1.86)

p = 0.378

p = 0.101

p = 0.276

a Questions on biogeochemical cycles of carbon, nitrogen, phosphorus, and water; the maximum score was 8. b The numbers include only students who took both the pretest and posttest; the posttest was not compulsory.

Table 3. NEETF Survey Scores for Treatment and Control Sections NEETF Attitude Scoresa Group (N)

NEETF Behavior Scoresb

NEETF Knowledge Scoresc

Pretest

Posttest

Gain

Pretest

Posttest

Gain

Pretest

Posttest

Gain

Comparison (112)

34.3

33.9

-0.37d

17.5

17.6

0.07

7.6

8.2

0.56

Treatment (70)

34.1

35.0

0.87d

17.8

18.1

0.37

8.0

8.4

0.47

a

Attitude scores were Likert-scale values; the maximum score was 42. b Behavior scores were Likert-scale values; the maximum score was 24. c Correct answers to knowledge questions earned 1 point (no points for incorrect answers); the maximum score was 11. d p = 0.017.

Gain scores for behavior and portions of the NEETF survey were not significantly different when compared between the two sections, nor were the knowledge gain scores. Discussion General Chemistry Knowledge General chemistry gain scores differed significantly at the p < 0.01 level; the treatment group scored an average of 0.6 of a point higher. Differences in general chemistry pretest scores most likely caused the differences in gain scores between the two sections. In other words, the environmentally focused class had more to learn. The small differences signify that real differences between the treatment and comparison groups were subtle at best, which makes sense given the subtle treatment. A more sensitive assessment with additional items may be useful in detecting modest differences in students' understanding of general chemistry. We are encouraged by these results and hope others will continue to explore how adding an environmental context to chemistry affects achievement in general chemistry. We suggest others use a less subtle treatment by including more environmental examples in class, adding environmental contexts to exam questions, and adding homework related to the environmental chemistry examples. Environmental Chemistry Knowledge Significant differences were not apparent in any of the groups when comparing scores on the environmental chemistry assessment. A greater number of items could have been used in both the pretest and posttest to more adequately assess gains in environmental chemistry knowledge. Eight items might not have been enough to probe understanding of four biogeochemical cycles. In addition, items assessing the environmental or real-life aspects of chemistry could have been included on midterm exams to stress the importance of the context material to students.


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NEETF Environmental Survey Significant differences in gain scores on the environmental attitude section of the NEETF survey indicate that students in the treatment section may have developed more pro-environmental attitudes as a result of their participation in a class that focused on environmental issues. Changes in environmental attitudes may eventually lead to changes in environmental behaviors. Homework on environmental behaviors such as keeping a trash diary (recording what one throws away in the course of a day) or computing a personal carbon footprint may be helpful in encouraging environmental behaviors. Implications and Further Study We encourage others to use quantitative designs like this one to explore how adding environmental contexts to introductory courses impacts achievement in chemistry, environmental mindset, and attitudes about chemistry. In this study, a subtle treatment led to modest results. We believe that if more environmental examples were used in class and more references were made to those examples during lecture, this treatment may lead to significant learning of general chemistry as students see chemistry as way of better understanding and resolving environmental problems. We also believe biogeochemical cycling is a relevant topic for developmental courses and should be included in discussions of a number of chemistry topics. The carbon cycle may be especially relevant because carbon sequestration is now becoming part of the national vocabulary. Perhaps the changes to the curriculum in this study were not enough to cause large differences between the two sections. To foster greater effects on student achievement and environmental mindset, larger changes in the curriculum need to occur. We concur with Uri Zoller's recommendations for embedding extensive environmental case studies as context for chemistry


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Research: Science and Education

content in general chemistry courses to increase environmental awareness (15). In addition to more environmental contexts for chemistry, more information about how students could ameliorate environmental problems may have had a greater impact on environmental attitudes as measured by the NEETF survey. The NEETF environmental literacy report recommended people receive concrete suggestions on how to change their behavior with an emphasis on how they can join others who are doing the same thing (18). NEETF found that citizens were more likely to engage in environmentally friendly behaviors if they thought their neighbors were also engaging in those behaviors. The report noted the positive correlation between environmental knowledge and most environmental behaviors. The more you know, the more likely you are to act to take positive steps for the environment (18). This NEETF report also emphasized that environmental knowledge develops over a lifetime as people are exposed to information in different contexts. Adding information about the environment to introductory chemistry courses can be a way to significantly increase learning in general chemistry as well as a source of environmental knowledge. Adding environmental contexts can also increase students' perceptions of how relevant chemistry is to real-life problems. Acknowledgment This research was supported in part through a grant from the National Science Foundation, CHE-0239461. Literature Cited 1. About the Chem Connections Project Web Page. http://www. wwnorton.com/college/chemistry/chemconnections/modules.html (accessed Dec 2009). 2. Gutwill-Wise, J. P. J. Chem. Educ. 2001, 78, 684–690. 3. Brown, W. C.; Eubanks, L. P.; Middlecamp, C. H.; Pienta, N. J.; Heltzel, C. E.; Weaver, G. C. Chemistry in Context: Applying Chemistry to Society, 5th ed.; McGraw-Hill: Dubuque, IA, 2006. 4. Nakhleh, M. B.; Bunce, D. M.; Schwartz, A. T. J. Coll. Sci. Teach. 1999, 25, 174–180.

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5. American Chemical Society. Chemistry in the Community, 5th ed.; W. H. Freeman: New York, 2006. 6. Winther, A. A.; Volk, T. L. J. Chem. Educ. 1994, 71, 501–505. 7. Burton, W.; Helman, J.; Lazonby, J.; Pilling, G.; Waddington, D. Salters Advanced Chemistry; Heinemann: Oxford, U.K., 2000. 8. Barker, V.; Millar, R. Int. J. Sci. Educ. 1999, 21, 645–665. 9. Barker, V.; Millar, R. Int. J. Sci. Educ. 2000, 22, 1171–1200. 10. Ramsden, J. Int. J. Sci. Educ. 1997, 19, 697–710. 11. Sutman, F.; Bruce, M. J. Chem. Educ. 1992, 69, 564–567. 12. Bennet, J.; Cornelia, G.; Parchmann, I.; Waddington, D. Int. J. Sci. Educ. 2005, 27, 1521–1547. 13. Swan, J. A.; Spiro, T. G. J. Chem. Educ. 1995, 72, 967–970. 14. Battles, D. A.; Franks, M. E.; Morrison-Shetlar, A. I.; Orvis, J. N.; Rich, F. J.; Deal, T. J. J. Coll. Sci. Teach. 2003, 32, 458–465. 15. Zoller, U. J. Chem. Educ. 2005, 82, 1237–1240. 16. Gilbert, J. K. Int. J. Sci. Educ. 2006, 28, 957–976. 17. NEETF. The 2000 NEETF/Roper Report Card Lessons from the Environment: The Ninth Annual National Report Card on Environmental Attitudes, Knowledge, and Behavior; National Environmental Education and Training Foundation & Roper Starch Worldwide: Washington, DC, 2001. 18. NEETF. Environmental Literacy in America: What Ten Years of NEETF/Roper Research Studies Say about Environmental Literacy in the U.S.; The National Environmental Education and Training Foundation: Washington, DC, 2005. 19. Garcia, T.; Yu, S. L.; Coppala, B. P. Women and Minorities in Science: Motivational and Cognitive Correlates of Acheivement. Presented at the Annual Meeting of American Educational Research Association, Atlanta, GA, April 1993; ERIC Document Reproduction Service No. ed359235, http://www.eric.ed.gov/ (accessed Dec 2009). 20. Turner, C.; Lindsay, H. A. J. Chem. Educ. 2003, 80, 563–568. 21. BouJaoude, S. B.; Giuliano, F. J. School Sci. Math. 1994, 94, 296– 302.

Supporting Information Available A 22-item environmental chemistry test on biogeochemical cycles is available. This material is available via the Internet at http://pubs. acs.org.


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Investigating the Impact of Adding an Environmental Focus to a

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