Service Learning Track in General Chemistry: Giving Students a

Jul 10, 2012 - Service learning is another type of experiential learning that is slowly gaining momentum in the sciences. There have been several repo...
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Service Learning Track in General Chemistry: Giving Students a Choice Kelley J. Donaghy* and Kathleen J. Saxton Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, New York 13210, United States S Supporting Information *

ABSTRACT: Experiential learning is a foundation in chemistry courses from the introductory-level course to upper-level courses through laboratory experiences. Service learning is another type of experiential learning that is slowly gaining momentum in the sciences. There have been several reports in this Journal on this pedagogy with respect to student engagement and success. However, widespread adoption of this teaching tool will not be achieved until suitable, scalable models for implementation of service learning in chemistry are available. Reported here is an example of a service learning aspect of a traditional second-semester general chemistry course where a separate grading scheme is created within the course called the Service Track. The logistics of running a course within a course, how the instructor uses Service Track teaching assistants, descriptions of the service projects, and how they are incorporated into the classroom, and the assessment of these projects, is described. KEYWORDS: First-Year Undergraduate/General, Curriculum, Physical Chemistry, Public Understanding/Outreach, Hands-On Learning/Manipulatives, Student-Centered Learning

Tell me and I will forget, show me and I will remember, involve me and I will understand.1 he benefits of experiential learning have been extensively used throughout chemical education in the form of laboratories connected to lecture courses. Another experiential learning option gaining attention is service learning, which has been defined as service to the community that connects with and supplements course content and course objectives.2 Going beyond the classic laboratory learning experience, service learning has the added benefit that students see coursework in context, engage with their college or university communities, which enhances their ability to make internship and research connections. Often seen in the humanities, art, architecture, and writing, there have been few reports in this Journal on the benefits of service learning in chemistry and only a few strategies about how to conduct chemistry service learning.2−11 Widespread adoption of this influential teaching tool will not be achieved until suitable, scalable, models for implementation of service learning in chemistry and methods for the assessment of the experiences are available. Although some strategies have been published for small classes, few have been published about service learning for larger classes: 100 or more students. Reported here is a unique approach to service learning that gives students a choice in the kind of course experience they desire; described is a separate grading scheme created within a traditional general chemistry course called the Service Track. The range of student interest and learning styles in a general chemistry classroom varies dramatically. Almost 20 years ago, the first reports about student-centered lecture halls began to appear in the literature, and a shift from the instructor as

lecturer, to a more student-centered, hands-on, collaborative learning lecture hall began.12 The challenge presented to an instructor, therefore, became how to embrace and use as many teaching methods as reasonable, to capture as many of these different learners, without sacrificing content and rigor. There is simply no “one-size-fits-all” approach to teaching and learning, and general chemistry is no exception. Students enrolled in all of our majors, except landscape architecture, are required to take general chemistry. The only course offered to this diverse set of students is a majors-level general chemistry course taught with sufficient rigor that students can succeed on the twosemester American Chemical Society standardized exam at the end of the second semester. The demographics of this course sequence rarely include more than 3% chemistry majors and it is taught by one instructor in three sections of 100−150 students (360 students in the first-semester general chemistry and 270 students in the second-semester general chemistry, although some majors only require the first-semester general chemistry). In an effort to find a way to make chemistry relevant and accessible, a “chemistry is everything” campaign is initiated in the first semester, which is executed through special topic vignettes during several lectures and an open-ended project at the end of the semester. During the second semester, an optional service project is offered: the Service Track. Community service is an essential part of the college experience at this university, where students routinely log more than 77,000 volunteer hours a year (averaging more than 30 h per student per year). However, service learning, which is

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details such as the end of the year conference, how many hours are required, a brief description of acceptable service projects, and a list of scheduled service events and projects. Students are given a week to sign the Service Track contract that indicates that there is no returning to the Traditional Track and they will be graded accordingly if they fail to fulfill hours, turn in the reflection paper, or participate in the mini-conference. The contracts that these students sign are only for how their grades are going to be evaluated. Student’s volunteer at their own risk but the service partners have insurance polices that cover volunteers at their sites, and the university is self-ensured. Project enrollment is also a priority at the beginning of the semester. The “groups f unction” on Blackboard is used for signups for each project. Transportation is often the limiting factor in the number of volunteers that each event can handle; therefore, the group information is preloaded with a detailed description that includes the date, time, and number of service hours; the event details; and the number of students that can be accommodated. To ensure that all students have an equal opportunity to sign up for their first choice of project, the groups are opened for sign-ups on a predetermined date at 6:00 a.m. The more popular projects can close out by 6:03 a.m. Often students on the Service Track will be involved in other projects with significant chemistry overlap, throughout the semester. These students are encouraged to bring their intended projects to the attention of the instructor for approval before assuming their projects will fit the definition of a servicelearning project for this course. For example, protests and social campaigns are not acceptable service learning projects for this course. Projects outside of the preapproved list are acceptable, but must fit the course objectives. These projects that students develop outside of the initial list add to the experience by giving students ownership of their work.

distinctly different that community service, is not for everyone. Therefore, the Service Track provides an avenue for students to choose the kind of learning experience they want to have in second-semester general chemistry. A separate grading scheme is offered for students wishing to take part in the Service Track that includes 15% for the service project and reduces some of the weight from hourly exams and the final. Those students who choose to have their course grade determined by exams and quizzes are on the Traditional Track. Course scheduling does not allow for a standalone Service Track section of the course. The Service Track was first offered as a choice in 2009; 77 students or 35% of the class enrolled. Three years later, 126 students or 56% of the class have participated; participants tell other students of their positive experience and nonparticipants tell others they wish they had participated. Furthermore, the Service Track students range from the top 10% based on the semester grades, who are looking to distinguish themselves and make important community connections, to the bottom 10% who are looking for a way to offset poor test-taking skills. One of the most important aspects of the Service Track is the community partnerships. Presented here is how the Service Track operates with one instructor and several undergraduate teaching assistants.

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THE SERVICE TRACK Service-learning, as defined by the National Service Learning Clearinghouse, is “a teaching and learning strategy that integrates meaningful community service with instruction and reflection.”13 Students participating in service learning do more than just community service; a stream cleanup, for example, is insufficient if all the students do is clean the creek. If they clean the creek, analyze the trash, and perform experiments about water quality, followed by sharing those results with the community, they are participating in service learning. Community service and service learning are distinguished by the learning associated with stream analysis, the reporting back to the community, and, finally, the reflection by the student about where this connects to their class and, more philosophically, to their career objectives. To achieve the service learning goals while on the Service Track, students are required (i) to complete 20 h of chemistry related community service, roughly 15% of the semester hours expected from students outside the classroom (3 credit hours multiplied by 3 h expected of traditional students for outsideof-class study time, multiplied by 15% multiplied by 15 weeks); (ii) write a reflection paper that relates their service back to the course objectives and content; and (iii) participate in a miniconference at the end of the semester, where they organize a group presentation on their projects for all members of the Service Track. Service partners are invited to the presentations and key members of the community often attend, enhancing the feedback given to the community.

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Service Track Teaching Assistants

Transportation, supervision, and safety are significant considerations in any project of this type. To facilitate this, past Service Track participants serve as Service Track teaching assistants (STAs). STAs enroll in a separate one-credit course called Chemistry Undergraduate Teaching Experience, and as part of their course, they help provide transportation and supervision. Typically, 5−8 STAs are needed per semester. The STAs must clear driver’s license background checks by the university police to drive university vehicles and participate in a teacher-training seminar provided to all undergraduate teaching assistants. Safety is stressed by the STAs and our community partners, who often have their own safety training. For events such as outreach to local schools and hands-on activities that are predominately run through the Service Track (not partners), the course instructor is always in attendance. The STAs are expected to contribute 50−60 h a semester to the Service Track as part of their course requirements. The STAs job is more than just chaperone, they help the Service Track students make the course connections, providing mentorship in chemistry, and they learn a new teaching method. The Service Track teaching assistants and the instructor are also responsible for helping with the assessment of the service projects. Although the STAs do not grade the Service Track students, they evaluate the projects in which the students participate. One of the STAs’ course responsibilities is to develop and refine a rubric for assessing service projects; the primary question is, do they meet the definition of a servicelearning experience in chemistry? STAs use the rubric from the

THE LOGISTICS

Enrollment

The execution of two grading schemes requires that students make a choice at the beginning of the semester and a contract is signed by both instructor and student acknowledging which grading scheme will be used to determine final grades. At the beginning of the semester students are told about the Service Track, this information is posted on Blackboard14 and includes 1379

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nanotechnology and present the activities to parents and camp participants. Through this project, the Service Track participants hone their understanding of a general chemistry principle, learn how to present it to a general audience, and gain critical on-the-job experience associated with museum work. Another event that Service Track students have participated in has been the MOST’s Nano-days. Again, students spend time working with museum staff and nanokits developing a presentation and research the science behind their kits and then act as docents and demonstrators for the museum during this week-long event. Demonstrations that the students learn at the MOST relate directly to course work, and whenever possible, these students are asked to present them in lecture.

previous year as a starting point. At the end of the semester, during the mini-conference, STAs fill out the rubrics for each project presented and coordinate a report that highlights the projects that met the second-semester general chemistry course objectives for service-learning and those that fell short of their mark. As a body of information is gathered, service projects evolve to highlight more of the chemistry or are cut from the list of available projects because of lack of service-learning aspects (lack of community engagement, for example) and replaced by others that students have engaged in outside of the preapproved list of projects that meet the goals of the servicelearning experience. The evaluation of the project is not a part of the students’ Service Track grade. Transportation

Transportation is provided, when needed, via the university’s motor pool. This university has a fleet of ∼30 vehicles, including hybrid vehicles and school buses that run on biodiesel generated by our students. The city has bus routes that run to some of our service projects, and whenever possible, students use public transportation. However, when public transportation is not an option, a school vehicle is utilized and is driven by one of the STAs or the course instructor.

Carpenter’s Brook Fish Hatchery

In 2009 it came to our attention that a local, county-run, fish hatchery was in jeopardy of closing its doors due to cutbacks in funding. The director of Carpenter’s Brook Fish Hatchery approached this university hoping to find interns and researchers to help take over some of the day-to-day operations. The hatchery currently stocks over 100 local streams and lakes with the 80,000 brook, brown, and rainbow trout it raises annually. The Service Track students have been able, over the past two years, to help keep the hatchery open (Figure 2). Because the hatchery is located approximately 20 miles from campus, a dedicated vehicle from the campus fleet shuttles between campus and the hatchery. Teams of 5−7 students leave campus throughout the day and work shifts between 2 and 6 h, many starting at 7:00 a.m. Students learn firsthand about the importance of water quality, dissolved oxygen, and general fish husbandry. Throughout the semester, stories are shared with other students about the failure of pond aerators and significant fish death due to lack of dissolved oxygen, usually precipitated because of a strong smell of triethylamine emanating from a participant hurrying back from their shift to class with no time to change or shower. This opens the discussion about the volatile organic compounds that are generated by the decomposition of proteins and can also be referred to during acid−base equilibria work.

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THE SERVICE PROJECTS Because this university has an environmental science focus, many of our projects revolve around water quality and resource management. One of the goals of service learning is to increase students awareness of future career options and to help them connect with community agencies.7 Service track partners include museums, fish hatcheries, citizen awareness groups, local professional organizations and elementary, middle, and high schools. Some of the more popular and extraordinary service projects that are available to our students are described (see Figure 1).

Adopt-a-Stream (Project Watershed/ACS)

In 2008 students in general chemistry entered an American Chemical Society (ACS) competition to adopt-a-stream in our area. The entire class, in collaboration with Project Watershed15 and Izaak Walton League of America environmental outreach program, learned how to do stream surveys for macroinvertebrates, chemistry, physical properties, and botany to access stream health. The class opened the event to the public and to the student population, and more than 300 people went to area streams to pick up trash and to do water quality assessments. This was the event that sparked the idea of the Service Track and is now the keystone event each year. At the beginning of the semester, 12 self-selected adopt-a-stream leaders begin the preparation for massive stream cleanups and survey initiatives on the second-to-last Saturday before the end of classes (Figure 3). These leaders guide the volunteers through the survey protocols they have learned from Project Watershed and that are now passed down through the STAs. The stream team leaders prepare an overview presentation for the water quality analysis and present it to the entire class and, in a separate meeting, to the whole campus, on the Friday before the Adopt-a-stream event.

Figure 1. Student volunteering at a horse rehabilitation farm where they learn the chemistry behind horse nutrition. Photo credit Emily Dengler.

The MOST

The Milton G. Rubenstein Museum of Science and Technology (the MOST) is a short bus ride from campus and has been an influential partner for many of our Natural History Interpretation majors. Students who participate at the MOST have taken part in two kinds of events: the Boy Scout and Girl Scout camp sleepovers and a week-long celebration of nanoscience. Service Track participants, in conjunction with museum staff, research and develop hands-on activities on an aspect of chemistry such as polymers, phase changes, or 1380

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Figure 2. Students working at the Carpenter’s Brook Fish Hatchery in Marcellus, New York. Photo credit Alex Palombo.

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CLASSROOM INCORPORATION The incorporation of the Service Track into the classroom is generally done as “real-life” examples of the subject being introduced. For example, stream surveys and water quality at the fish hatchery relate directly to the topics of kinetics, solutions, and equilibrium. When these topics are discussed in lecture, the hatchery is used as an example and students working on these projects are encouraged to tell the rest of the class what they worked on that week. Dissolved oxygen in water is always an interesting discussion and comes up any time there is a large fish kill due to an aerator malfunction. Electrochemistry is also present in the water quality work; students use ion-selective electrodes for dissolved oxygen, nitrates, pH, and chloride. Polymers are covered in the second-semester general chemistry curriculum and students who participate in the hands-on-activities are asked to demonstrate slime and alginate worms to illustrate polymer cross-linking. Science fair judging has, as its root, an understanding of the scientific method, and after each judging event, students in the track are asked to talk about the event, highlight a few new things they learned, and to describe the best posters and why they were the best posters. At the end of the semester while reviewing for the final exam, the instructor uses all the service events as examples for the chemistry learned throughout the semester. It serves as a unique way of showing their classmates at work and putting the chemistry in context. Further, these 5−10 min discussions or demonstrations add an extra dimension to the course for both Traditional Track students and Service Track students.

Figure 3. EDTA titration for calcium ion concentration done streamside. Photo credit Kathleen J. Saxton.

Science Fairs

Local science fairs often have problems finding enough judges to ensure that all students participating have someone to interview them about their projects. Science fair coordinators have turned to our Service Track participants as judges for their middle and elementary school fairs. The Service Track participants see the scientific method in action and learn to recognize good projects from poor projects by interviewing and asking questions of the fair participants. In the process, the Service Track students often learn something new about science and about what makes an effective poster presentation, and the student presenter is interviewed by several interested judges. Students who work these fairs return discussing the scientific method and its relationship to the laboratory course associated with second-semester general chemistry lecture.

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ASSESSMENT

Assessment of the Service Track takes several forms; program assessment by the participants, assessment of the service projects, and assessment of the participants themselves. The

Table 1. Evaluation of the 2011 Service Track Student Response (%)b Statement I had ″no problem″ finding 20 h of service-learning activities for the semester. To what extent were you able to relate the service-learning activities to the course objectives?a Taking part in the Service Track had a positive influence on your attitude toward second-semester general chemistry lecture. Taking part in the Service Track increased your success in the course. Taking part in the Service Track increased your confidence in the course material. Taking part in the Service Track increased your interest in interacting with the professor and therefore encouraged you to seek her out during office hours. We should continue to offer the Service Track next year in second-semester general chemistry.

Strongly agree

Agree

Neither agree or disagree

Disagree

Strongly Agree

55.1 18.56 36.08

38.78 74.23 43.3

3.06 − 16.49

2.04 6.19 2.06

0 1.03 1.03

46.39 1.03 10.31

40.21 35.05 37.11

9.28 41.24 39.18

3.09 19.59 10.31

0 2.06 2.06

87.63

11.34

2.06

0

0

a

The students responses were strong connections, some connections, no connections, and no connections whatsoever. bThe numbers do not add to 100 because some students failed to answer all questions; the percents are based on the total number of students who took the survey. 1381

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re-evaluated and, if necessary, excluded from the offerings for the next iteration of the Service Track. The basics of this rubric remain the same with slight modifications made each year. It is expected that this rubric will reach a static state and STAs will work on a new aspect of teaching and learning associated with the Service Track.

students evaluate the program from the students’ standpoint, the STAs and instructor are responsible for evaluating the quality of the projects, and the instructor and course graduate teaching assistants16 evaluate the students. Assessment of the Service Track by Participants

Service Track participants are given a survey specific to the program each year and are asked key questions about the program. From these responses, we have been able to refine the program and to increase the crossovers in the classroom and the connections between the projects and the course content and objectives. The results of the 2011 Service Track survey (administered through Blackboard) are shown in Table 1; full student responses to free answers can be found in the Supporting Information. Seventy-five percent (97/126) of all Service Track participants responded no incentives were used to encourage students to participate. The survey results indicate that more than 90% of the participants surveyed had no problems fulfilling their 20 h and that they were able to make some connections to the course objectives (master fundamental chemical concepts, gain an appreciation for and an ability to use the scientific method, develop problem-solving and analytical skills, and create a foundation for future scientific study). Despite the fact that 100% of the general chemistry sequence consists of science majors, 97% of the class is composed of nonchemistry majors; thus, the course still suffers from the lack of interest, fear, and the “can’t do this” attitudes prevalent in introductory nonmajors courses. It is often difficult to “sell” the idea that chemistry is a central science and essential to all scientists and citizens. One of the benefits of the Service Track is that it forces students to think about how chemistry is everywhere and how it influences all aspects of life. The 2011 survey indicates that 79% of our respondents agree that the Service Track has had a positive influence on their attitude toward chemistry and that 86% of them feel that it has led to an increase in their ability to succeed in the course and 87% strongly agreed that the Service Track should continue to be offered.

Participant Assessment

Evaluation of the students’ individual work is carried out by the instructor and course graduate assistants who evaluate the students’ exams and quizzes (the instructor does not believe in peer-on-peer grading). The average student in the Service Track sees an increase in their overall letter grade by a half a letter grade (4−6 points numerically). The reflection papers, though, indicate that while the grade boost in the end is moderate, a majority of the students learn a lot more about themselves and their world through this experience. For many students, this has changed their outlook on the careers and has created community contacts for others. Many of our community partners have summer internships that are highly competitive. Both the Service Track participants and the STAs compete very well for these positions and credit having been part of the Service Track as encouraging them to apply and to propelling them further than other interns.

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CONCLUSIONS The second-semester general chemistry Service Track is a highly successful program. It serves to reinforce general chemistry course content while helping students reach the course objectives. The survey results and reports from service partners indicate that students are learning about problem solving, improving analytical ability, and as an added benefit, practicing presentation skills inside and outside of class. Although there is always room for improvement, particularly to strengthen the course connections, the Service Track works. The most difficult part of administrating the course took place in the first year of the course; finding service partners becomes easier every year and returning STAs help with continuity. Although there is no direct evidence that the Service Track increases the number of science majors arising from the community groups that are interacted with, it is increasing the number of people exposed to chemistry and consequently decreasing “chemistry phobia” often perpetuated by the news media. Administering the two tracks within a course is not difficult and it is well received by both Traditional Track and Service Track students; they feel like they have some control over their learning experience with respect to which track they choose. As far as the demands on the instructor, the extra 20 h per semester of administrative oversight (not including the time spent at different events) provides an innovative and highly accessible approach to teaching introductory chemistry topics while enhancing student self-esteem in a course often derided for breaking self-esteem.17 The Service Track asked the next generation of citizens to step away from their computers, iPhones, and other electronic media for a few hours and in the last three years, more than 6,460 h of chemistry related community service has been accomplished!

Service Project Assessment

Assessment of the individual service projects is undertaken by the STAs and instructor. Each year, the STAs, as part of their course requirements, refine a rubric for assessing the service projects with respect to meeting course objectives and highlighting key course content. The questions to which the 2011 STAs sought answers from the presentation of the students at the mini-conference included: • Are any of the following topics relevant to the class content observed within the project: polymers, kinetics, nuclear chemistry, equilibrium (acid−base), buffers and titrations, ionic equilibrium, thermodynamics, and electrochemistry? • Did this project allow the student to work with or observe the chemistry directly in a hands-on fashion? • Can the chemistry involved be easily identified by both students and the members of the community? • Does this project promote chemistry in the community? • Does this project benefit the community? • What aspects of chemistry do you feel were promoted and how do you feel the community can benefit from such activities in the future? Each project is scored on the above criteria based on a 1−5 scale (1 being worst and 5 best); projects scoring low are then

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ASSOCIATED CONTENT

* Supporting Information S

Course syllabi for second-semester general chemistry and the STA course; Service Track handouts; the Service Track contract; hours log sheet; events listing for 2011; specific 1382

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information for Carpenter’s Brook Fish Hatchery; project assessment rubric; student survey results; and two student reflection papers. This material is available via the Internet at http://pubs.acs.org.

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS The authors wish to thank our service partners without whom the 2011 Service Track would not have been so successful: Betty Jones of the Milton J. Rubenstein Museum of Science and Technology, Mat Webber of Project Watershed, Travis Stanek of Carpenter’s Brook Fish Hatchery, Ellen Everly and Jennifer Proper of Fabius Pompey Elementary School, Sally Mitchell at East Syracuse Minoa High School, the Syracuse Section of the American Chemical Society, and the Chemistry Department of SUNY-ESF for their financial support.

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REFERENCES

(1) The origin of this quote is unclear it has been attributed to Confucius, Native Americans and others. (2) Weigand, D.; Strait, M. J. Chem. Educ. 2000, 77, 1538−1539. (3) Cartwright, A. J. Chem. Educ. 2010, 87, 1009−1010. (4) Kalivas, J. H. J. Chem. Educ. 2008, 85, 1410−1415. (5) Sutheimer, S. J. Chem. Educ. 2008, 85, 231−233. (6) LaRiviere, F. J. J. Chem. Educ. 2007, 84, 1636−1639. (7) Esson, J. M.; Stevens-Truss, R.; Thomas, A. J. Chem. Educ. 2005, 82, 1168−1173. (8) Draper, A. J. J. Chem. Educ. 2004, 81, 221−224. (9) Hatcher-Skeers, M.; Aragon, E. J. Chem. Educ. 2002, 79, 462− 464. (10) Weigand, D.; Strait, M. J. Chem. Educ. 2000, 77, 1538−1539. (11) Kesner, L.; Eyring, E. M. J. Chem. Educ. 1999, 76, 920−923. (12) Angelo, T. A., Ed. Classroom Research : Early Lessons from Success; New Directions for Teaching and Learning, No. 46; JosseyBass: San Francisco, CA, 1991 . (13) See for example: (a) Dallimore, E.; Rochefort, D. A.; Simonelli, K. In Experiential Education: Making the Most of Learning Outside the Classroom; Qualters, D. M.; Wehlburg, C. M., Eds.; New Directions for Teaching and Learning, No. 124; Jossey-Bass: San Francisco, CA, 2010; pp 15−23 (b) National Service Learning Clearinghouse, http:// www.servicelearning.org/what-service-learning (accessed Jun 2012). (14) Blackboard is an online course delivery program provided to all instructors at SUNY-ESF. Open-source online course development and delivery platforms are available and can be used to help manage this aspect of the course. (15) Project Watershed, http://www.projectwatershed.org/ (accessed Jun 2012). (16) The graduate assistants are the teaching assistants for the whole course, service and nonservice track students. They grade and hold recitations and office hours. Other than grading the final presentation, they are not involved with the service track unless they choose to be. (17) Brooks, D. J. Chem. Educ. 1993, 70, 135−139.

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