Incorporating Student-Designed Research Projects in the Chemistry

Jun 2, 2011 - Division of Chemical Education, Inc. 1069 ... ABSTRACT: Although many chemistry students at small liberal arts colleges participate in ...
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Incorporating Student-Designed Research Projects in the Chemistry Curriculum Devin S. Iimoto*,# and Kimberley A. Frederick† #

Department of Chemistry, Whittier College, Whittier, California 90608, United States Department of Chemistry, Skidmore College, Saratoga Springs, New York, 12866 United States



bS Supporting Information ABSTRACT: Although many chemistry students at small liberal arts colleges participate in undergraduate research projects with faculty members, they do not get much experience framing their own research questions and designing their own projects, which is an important part of science. We have implemented a developmental process to help students design and execute their own research projects in a two-course sequence: seminar in the fall and an integrated laboratory in the January term as a capstone experience in the chemistry curriculum. In seminar, students read scientific literature to generate an unanswered question that becomes the basis for a project proposal. Students then compare and contrast various methods to answer the question and propose a project. In the integrated laboratory, students execute the project where they troubleshoot experiments, collect and interpret data, and draw conclusions. Assessment of final papers and student course evaluations indicated that the students met the above goals. Overall, this educational experience can be implemented at other small liberal arts colleges and elements of this project could be adapted at a larger college or university. KEYWORDS: Upper-Division Undergraduate, Curriculum, Interdisciplinary/Multidisciplinary, Laboratory Instruction, HandsOn Learning/Manipulatives, Problem Solving/Decision Making, HPLC, Undergraduate Research

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aboratory work is essential for a young chemist to learn how to think like a scientist and to understand how new scientific knowledge is created. The American Chemical Society’s Committee on Professional Training (ACS-CPT) suggests that a rigorous undergraduate education progressively develops more sophisticated analytical and laboratory competencies, which includes the ability to perform “... simple stepwise manipulations performed according to a prescribed sequence, but progress to activities that require decision-making about appropriate experimental design and data interpretation/analysis required to answer specific chemical questions”.1 We have developed a two-course sequence required for all chemistry and biochemistry majors that develops and provides opportunities to demonstrate all the competencies suggested by ACS-CPT. In the first course, seminar, students focus on literature work and develop an original scientific question that they pursue experimentally in the second course, integrated laboratory. In addition to meeting the ACS-CPT guidelines, these two courses address many pedagogical limitations and go beyond strategies to improve laboratory instruction cited by others in the literature. For example, most laboratory courses employ what Domin2 calls the expository laboratory instruction style in which students work through one or more experiments with a set of given instructions to obtain results that reinforce a particular chemical principle learned in lecture. This “cookbook” approach to laboratory instruction teaches students certain basic laboratory techniques and how to collect data and analyze the data, but it does not engage students in a creative endeavor. Other styles of laboratory instruction such as inquiry, discovery, and problem-based laboratory exercises access some higher-order thinking skills, such as evaluation and analysis, Copyright r 2011 American Chemical Society and Division of Chemical Education, Inc.

where students plan their own experiments (problem-based and inquiry) and evaluate the meaning of their data as it relates to a particular chemical principle (inquiry and discovery).2 Although the above approaches engage students at the higher cognitive levels of Bloom’s taxonomy3 and Perry’s model of intellectual and ethical development4 and are valuable learning experiences for students, they do not cover the entire thought process involved in scientific investigation. For example, in many problem-based approaches, a well-defined problem is given to the student by the faculty member,5 9 so the student does not generate the question. Even students who do undergraduate research are typically working on a faculty member’s project and not one that the student has created and designed. Thus, we have implemented a developmental model to help students design and execute their own research project in two capstone courses: seminar and integrated laboratory. These courses have an enrollment of 4 9 students per year of whom slightly more than half are female students. This article details the course design and goals along with our assessment efforts based on final paper analysis and student evaluations. This type of experience may be best suited for upper-level chemistry students at institutions with low student-to-faculty ratios, but features of this project could certainly be adapted to larger institutions.

’ DESCRIPTION OF THE SEMINAR The developmental process for a student’s self-designed research project is initiated in a two-credit hour seminar course, offered in the fall of the final year. The course is subdivided into Published: June 02, 2011 1069

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Table 1. Stages in Developing a Student Research Proposal and Course Schedule Stage Read and analyze a scientific journal article

Present comprehensive

Week

Topic

Assignment

1

Research topic/literature search

Select a topic/select an article

2

How to give an oral presentation

Bring articles for approval

3

Oral presentation and paper (group 1)

Specific journal article

4

Oral presentation and paper (group 2)

Specific journal article

5

No class; Individual meeting with professor to discuss topic of interest

background information on a

6

Oral presentation and paper (group 1)

Background information on topic

specific topic of interest

7

Oral presentation and paper (group 2)

Background information on topic

8 9

How to design a research proposal Formulate question/find method No class; Individual meeting with professor to discuss question/methods

Final research proposal

10

Peer group discussions of proposal

11

Rough draft of research proposal due

12

Rough drafts returned

Look up chemicals and supplies

13

List of chemicals and supplies due

Write final proposal

14

Final research proposal due; oral presentation and paper

three major assignments that guide students through the experimental design process while introducing and developing a series of cognitive and practical skills The course outline is presented in Table 1. In the first assignment, students develop their ability to critically read and analyze a scientific journal article. Students are given two weeks to search the literature and choose one article of particular interest to them that they analyze and summarize in a 4 5 page paper and in a 10 12 min oral presentation to the class. Students are instructed in how to do a literature search using SciFinder and PubMed databases. Instructor approval is needed for the first journal article to ensure that it contains sufficient experimental data to discuss. Because most students have given only a few, if any, scientific oral presentations at this point, they are provided with both oral and written suggestions for delivering a successful oral presentation. In addition, their paper and oral presentation must provide some background information on the journal article topic, present the authors’ hypothesis or question, explain the purpose for each of the major experiments, and explain the data and the conclusions drawn from the data. Students also critique the experimental design and interpretation of the data. Thus, in addition to learning how to read and analyze a journal article, students continue to develop their scientific writing, literature searching, and oral presentation skills. The next assignment requires students to conduct a literature survey and summarize a larger area of research. Ideally, this is an expansion of the topic identified in their first assignment. In this exercise, students present detailed information on a focused topic. Thus, rather than presenting general information on a broad topic such as cancer, signal transduction, or phosphorus chemistry, students focus on more specific topics such as novel treatments for cancer, specific mechanisms of signal transduction, or novel phosphorylating agents. Students pull together information from many journal articles to present what is known about a particular field. They are encouraged to compare and contrast experimental approaches, identify aspects of the topics that are commonly accepted, and any competing hypotheses or contradictory results. By focusing student attention on a specific topic, they begin to question what is not known about the topic. Students are given 2 3 weeks from the time of the first presentation to prepare for the second presentation,

Write rough draft

which involves both a 5 6 page paper and a 12 15 min oral presentation. The final project in the seminar course requires students to think about a specific question and an experimental procedure that they then pursue in the integrated laboratory course. In addition to the background information, the specific question being answered, and an experimental method to answer the question, students also submit a list of materials and supplies needed for the project, identifying what items needs to be ordered, from which company, and the approximate price. This part of the proposal helps students realize the cost of doing science, and it allows the department time to order the chemicals and supplies they need to do the project. Each student has been told that they can spend about $300 for his or her project. Mechanisms are in place to help the students work through the process of developing a scientific experiment that can be done in a few weeks on a minimal budget with resources available in the chemistry department. First, students are encouraged to read more journal articles. Also, in lieu of one class meeting, students meet with the faculty member in a one-on-one meeting to discuss their ideas. In these meetings, the instructor helps the student focus the question appropriately and identifies possible methods to answer the question. In addition, the instructor can point out any potential pitfalls with a particular project or if a project is simply not executable. In another class period, students bring the focused question for their project and an outline of an experimental procedure for peer evaluation. Students review each other’s projects and seek additional faculty input. Students submit a rough draft of their proposal two weeks before the final paper is due so that the instructor can read over the draft and make appropriate suggestions on any residual experimental issues but also on the style and structure of their proposal. The seminar finishes when the students submit a polished, final 8 12 page draft of their research proposal and give a 15 min oral presentation. To help students successfully design an appropriate project, flexibility is absolutely critical. In the initial stages of the project, students who are uncertain about their area of interest may choose to change their field of focus and the second presentation (literature survey) can be on a different topic from the topic of the first presentation. If a student is having a difficult time trying to generate an appropriate project, a faculty member can refer the 1070

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Journal of Chemical Education student to particular articles or journals that may be good starting points. We have found that articles in the Journal of Agricultural and Food Chemistry can lead to an executable project. Also, during the middle stages of the project, a student may not know what direction to take the project. The faculty member can ask pertinent questions that help guide the student in an appropriate direction, such as finding a more executable or effective method to answer their research question or even tell the student that he or she needs to find a different research question altogether. We have found that students can still be successful changing the topic as long as the student understands the work that needs to be done to develop the final proposal from scratch. In addition, the instructor can refer the student to another faculty member in the department if the project is too far outside his or her area of expertise to appropriately guide the student. This is perhaps one of the tougher aspects of teaching the course because it involves the willingness of other department members to help out when needed.

’ DESCRIPTION OF THE INTEGRATED LABORATORY The developmental process is completed in the integrated laboratory, a three credit-hour course taken during the threeweek January term, where students execute the project they proposed in the fall semester seminar course. This course is taught by a team of two faculty members in the chemistry department, one of whom is the same faculty member who taught the seminar course. The January term is a perfect time to do a laboratory-intensive course because students take only one course and are in the laboratory from 9:30 a.m. until about 4:30 p.m. with a break for lunch. However, this type of course could work in a semester format. Success in this section of the course relies on effective use of time. Students are required to be prepared and know what experiments they plan to try before they come to lab each day to avoid wasting time. As in any research project, students encounter experimental issues in the first few days that they must troubleshoot. Upon collecting data, students interpret their results and make decisions about what to do next. Because they only have three weeks to do their experiments, students only obtain preliminary results and in many cases obtain negative results or indeterminate results. At the end of the January term, students present their experimental data in a paper following ACS journal format and give an oral presentation. In the last part of their report, students who obtained positive results explain what they would do next if given the chance to extend their project, and students who obtained negative or indeterminate results explain how they would troubleshoot their experiments or provide alternate methods to answer their question. ’ EXAMPLES OF STUDENT PROJECTS Examples of student projects can be found in Table 2. Three projects are briefly described. A project that yielded positive results, which were eventually presented at an American Chemical Society meeting in March 2009,10 involved determining if various Echinacea herbs have antibiotic activity. The student developed the project in seminar based on his interest in herbal medicines and health related issues. He discovered in his literature search that, although there was a lot of evidence that supported Echinacea’s ability to stimulate the immune system, there was only one reference with little information or data on Echinecea’s antibiotic properties. Thus, he proposed to

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Table 2. Examples of Student Projects (2005 2009) • Antibiotic Activity of Echinacea Herb in Cultures of Escherichia coli and Staphylococcus aureus • Polyphenolic Compounds in Brazilian and Pine Nuts • Does Wild Yam Metabolically Inhibit CYP3A4 Activity? • Methyl Salicylate Detection and Quantification in European Honeybees Sprayed with Methyl Salicylate Containing Sugar Syrup • Determining the Presence of the Glutamate Transporter EAAC1 in Rat Pancreatic Glands • Evaluation of Benzene and Toluene in Orange Soda • Utilizing House Plants to Naturally Detoxify Ozone in the Domestic Sphere • Detection of Eag1 Potassium Channels Using a Western Blot Technique • Comparison of the Amount of Vitamin D3 in Cold and Heated Milk • Colorimetric Determination of Lactose in Regular Fat-Free Milk and Lactose-Free Fat-Free Milk • Valerian and Enzymatic Activity on L-Glutamic Dehydrogenase • Resveratrol Found in Wine May Not Inhibit HMG-CoA Reductase • Dihydrofolate Reductase Inhibition in Relation to Antimalarial Drugs • 1,3-Dimercaptobenzene and its Affect on Polyphenol Oxidase • Analysis of Water Runoff Around Whittier College • Observing the Effects of Chinese Medicinal Herbs on Fatty Acid Synthase Activity • Comparing Water Quality Between the Tap and the Water Treatment Plant

test various Echinacea extracts, obtained from several different varieties of Echinacea plants using different solvents for extraction, on two different types of bacteria. The student found that a couple of varieties of Echinacea herb extracts showed antibiotic properties toward Staphylococcus aureus, a Gram-positive bacterium, but not against Escherichia coli, a Gram-negative bacterium. The student was motivated to work on this project beyond the January term and, upon analyzing the extracts on a gas chromatograph mass spectrometer (GC MS), the student identified compounds that were more abundant in the antibiotic active Echinacea herbs than the antibiotic inactive herbs and that these compounds potentially had an aromatic structure to them. Another student was interested in testing if wild yam extracts, an herbal medicine, would affect the metabolism of prescription medications in the body by determining if these extracts inhibited the activity of cytochrome P450 3A4 (CYP3A4). She developed this project in seminar after researching the literature on her interests in herbal medicines and pharmacology and discovered that herbal medicines can potentially interfere with the efficacy of physician-prescribed medications through the enzyme cytochrome P450. Because wild yam had not been investigated with regards to its effect on cytochrome P450, she tested wild yam extracts on the activity of a specific isozyme of cytochrome P450 (CYP3A4). She used estradiol as the substrate for the enzyme, and she detected the estrone product using a C18 reverse-phase column on a high-performance liquid chromatograph (HPLC). Her preliminary results indicated that the wild yam extracts inhibited CYP3A4 and thus could potentially affect the bioavailability of other drugs. A third project involved determining the presence of ellagic acid, a polyphenolic compound, in the pellicle and kernel of Brazilian and pine nuts. The student developed this project based on her interest in nutrition and discovered that various nuts 1071

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Table 3. Assessment of Student Work by Two Faculty (2009 2010)

Outcome

a

Table 4. Aggregate Results from Student Course Evaluations for Integrated Lab (2007 2009)

Average

Average

Scorea

Scorea

(n = 5)

Question

(n = 17)

1

Provides a compelling rationale for project

4.2

Did you improve your ability to plan your experiments?

4.35

2

Clearly states a hypothesis or question

3.4

Did you improve your ability to troubleshoot experiments

4.18

3

Designs an effective and executable method

3.1

when things did not work as planned?

4

Effectively executes the experiments

4.0

Did you improve your ability to analyze/interpret data?

5

Reasonably interprets data

3.6

Are you more confident in your lab skills working in lab?

4.24

6

Proposes a logical future direction to project

2.7

How much did you learn in this course?

4.34

Five-point grading scale with 5 as the highest score.

contain helpful antioxidants that provide protective effects against cancer and other diseases. Polyphenolic compounds are antioxidants that are found in varying quantities in nuts and, although certain nuts had already been tested, Brazilian and pine nuts had not been tested. This student proposed to measure the levels of ellagic acid in Brazilian and pine nuts because the pure form of ellagic acid, used as a standard, was relatively inexpensive. The student ran nut extracts on a C18 reverse-phase column on an HPLC to quantify the amount of ellagic acid; her preliminary results indicated that Brazilian nuts contained more ellagic acid than pine nuts and that per gram, the Brazilian nut pellicle contained more ellagic acid than the kernel.

’ ASSESSMENT To assess the degree to which the students met the learning goals of designing, executing, and evaluating a novel scientific project, instructor observations, a systematic review of the final papers, and student feedback on the integrated laboratory course evaluations were compiled. Instructor observations identified significant growth in cognitive and practical skills. In addition, the level of student competency in the two-course sequence was determined by assessing the final papers from each course based on a rubric that evaluated students on six important outcomes, three in seminar and three in integrated laboratory (Table 3). Two faculty evaluated five student papers from the last two years using this rubric; the students ranged in ability from the bottom to the top of the class. Statistical analysis using Cohen’s kappa rating (0.64) indicated that there was substantial agreement between the two faculty in evaluating the student work and that the above analysis is not due to chance. However, if outcome 3 is removed from the data set, then Cohen’s kappa rating goes up to 0.73, indicating an even stronger agreement between the two raters. Students scored well for outcome 1 (provides a compelling rationale for the project) and outcome 4 (effectively executes the experiments for the project). For outcome 1, this means that the students did a fairly thorough job of reading the peer-reviewed literature, clearly explained prior research, and thus provided a good context for the importance of their proposed project. For outcome 4, this means that the students effectively performed their experiments and collected appropriate data with minimal input from the instructor. Students scored moderately well on outcome 2 (clearly states a hypothesis), 3 (designs a executable and effective method), and 5 (provides a reasonable interpretation of the data). For outcome 2, this means that the project question or hypothesis is novel, that

a

4.06

Five-point grading scale with 5 as the highest score.

the question or hypothesis is generally well articulated, and that the question or hypothesis makes sense with the background information, but that there might be one or two gaps in articulating that connection. For outcome 3, it means that the proposed experimental method is capable of providing data that can answer the question, but might have some flaws or omissions in some specific procedural steps in the project proposal. Finally, for outcome 5, it means that the students were able to perform most calculations, interpret the data, and draw conclusions, but with significant help from the faculty member. Finally, students scored fair on outcome 6, which is proposing a logical future direction to the project. This was an area that students did not put as much effort into as the instructors would have liked, and thus while some students gave detailed ideas as to what they should do next, several students gave only vague and general ideas. Additional instruction in this area would likely increase the student’s level of achievement. Information on the ratings scale for each outcome can be found in the Supporting Information. Overall, the assessment of student work indicates that students were able to generate and execute a novel project fairly effectively as long as there was significant faculty guidance such as what is provided in seminar and the integrated laboratory. We also examined students’ self-reported gains in the integrated laboratory course according to the course evaluations. Of the 17 surveyed students (9 were female and 8 were male), 4 of these students are currently doing graduate work in chemistry, biochemistry, or biology. Overall, these students say that they enjoyed the freedom to plan and do their own experiments. Some student comments included • “I enjoyed the atmosphere of the lab. It was a great learning environment and taught me how to think and react using the knowledge gained within the course and from other courses taken” • “The freedom to plan our experiment” • “How open-ended it was allowing students to pursue various interests”. The students also self-reported that they improved their ability to plan and troubleshoot their experiments and to analyze and interpret their data, and they improved their confidence in the laboratory (see the aggregate results from the course evaluation forms in Table 4.) Students’ major complaint was that there were time constraints on doing their projects because we had previously required students to do instructor-led integrated experiments prior to doing their independent project. Thus, when asked what 1072

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Journal of Chemical Education they liked least about the course, the comments included the following: • “Allow students to do their experiment the entire January term. Don’t have a lab before”, “Give more time to do personal experiment-cut out one of the other ones...” • “It will be very helpful to dedicate more time to the individual projects”. In fact, when we reduced the number of nonproject experiments from two to one, which allowed the students to spend more time on their projects, the course evaluations improved from an average of 4.07 to 4.67 on all questions asked on the course evaluation form. We have since decided to focus the entire integrated laboratory on the students’ independent projects. Thus, our capstone experience, to a measured extent, allows students to experience the joys and frustrations that accompany scientific research. Students gain confidence in their ability to work in the laboratory and to design their own project and they overcome their initial fears toward this creative activity. Because past students have commented that they would like more time to pursue their projects, we addressed this issue by focusing the entire January term on the independent project. Nonetheless, these students found the seminar and integrated laboratory experience enriching to their intellectual growth as scientists and an important part of their education.

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(3) Taxonomy of Educational Objectives: The Classification of Educational Goals; Bloom, B. S., Ed.; Susan Fauer Company, Inc.: Chicago, IL, 1956; pp 201 207. (4) Perry, W. G., Jr. Forms of Intellectual and Ethical Development in the College Years: A Scheme; Holt, Rinehart, and Winston: New York, 1970. (5) Prince, M.; Felder, R. J. Coll. Sci. Teach. 2007, 36, 14–20. (6) Cessna, S. G.; Kishbaugh, T. L.S.; Neufeld, D. G.; Cessna, G. A. J. Chem. Educ. 2009, 86, 726–729. (7) Ram, P. J. Chem. Educ. 1999, 76, 1122–1126. (8) Adami, G. J. Chem. Educ. 2006, 83, 253–256. (9) Richter, M. M. Chem. Educator 2001, 6, 21–24. (10) Irvine, K., Isovitsch, R., Iimoto, D. Abstracts of Papers, 237th ACS National Meeting, Salt Lake City, UT, United States, March 22 26, 2009.

’ CONCLUSIONS We have reported the implementation of a two-course sequence required for all chemistry majors that challenges students to go through every aspect of experimental design, implementation, and evaluation in a way that authentically models scientific research. On the basis of instructor and student assessment, this sequence provides an opportunity for students to develop and demonstrate many of the key competencies for a rigorous undergraduate chemistry education. ’ ASSOCIATED CONTENT

bS

Supporting Information Rubric for assessing student’s ability to propose and execute a project. This material is available via the Internet at http:// pubs.acs.org.

’ AUTHOR INFORMATION Corresponding Author

*E-mail: [email protected].

’ ACKNOWLEDGMENT This work was funded in part by NSF-CCLI Award 0410423. We would like to thank Ralph Isovitsch in the Whittier College Chemistry Department for assessing five student projects. We would also like to thank Mary Campa in the Skidmore College Psychology Department for her help with the statistical analysis of the assessment data. ’ REFERENCES (1) Committee on Professional Training; Undergraduate Chemistry Programs. http://portal.acs.org/preview/fileFetch/C/CNBP_024263/ pdf/CNBP_024263.pdf (accessed Apr 2011). (2) Domin, D. S. J. Chem. Educ. 1999, 76, 543–547. 1073

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