Teaching Collaborations and Scientific Practices through a Vertically

Laboratory Experiment Cite This: J. Chem. Educ. XXXX, XXX, XXX−XXX

pubs.acs.org/jchemeduc

Teaching Collaborations and Scientific Practices through a Vertically Scaffolded Biodiesel Laboratory Experience Kelly Y. Neiles,*,† Geoffrey M. Bowers,† Daniel T. Chase,† Amanda VerMeulen,‡ Douglas E. Hovland,† Elan Bresslour-Rashap,† Leah Eller,† and Andrew S. Koch† †

Department of Chemistry and Biochemistry and ‡Library and Media Center, St. Mary’s College of Maryland, St. Mary’s City, Maryland 20686-3001, United States

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S Supporting Information *

ABSTRACT: Guiding students to become practicing scientists entails teaching them the specialized ways of collaborating, writing, and thinking that these professionals utilize every day. Laboratory experiences provide unique opportunities for student-centered curricular activities that mimic these skills. The biodiesel laboratory experience described here connects previously published biodiesel exercises in an intentionally scaffolded experience that models for students the types of collaboration and communication skills they will need if they choose to enter a STEM profession. The collaboration is vertically scaffolded to span multiple courses (general chemistry, organic chemistry, and physical chemistry) with opportunities for future connections with additional upperdivision courses. The experience is writing intensive with a focus on both scientific writing through formal laboratory reports and writing for communication with nonscientists. By encountering this experience repeatedly throughout their chemistry coursework, students have the opportunity to develop the habits of working scientists. KEYWORDS: First-Year Undergraduate/General, Second-Year Undergraduate, Upper-Division Undergraduate, Curriculum, Laboratory Instruction, Collaborative/Cooperative Learning, Communication/Writing, Inquiry-Based/Discovery Learning, Calorimetry/Thermochemistry, Catalysis, Materials Science, Physical Properties, Student-Centered Learning

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writing, and reasoning.9 Thus, for students to be successful in the sciences, they must learn these specialized skills through intentionally designed, well-scaffolded learning experiences where students engage meaningfully in the processes involved in science. The NRC Framework and NGSS outline eight scientific practices with which K−12 students should engage.9,10 The Three Dimensional Learning Assessment Protocol (3DLAP), a protocol developed for higher education, further refined this list and provided a way to determine which practices are present in an experience.11 As students engage in these practices, they have the opportunity to learn the methods of thinking that scientists use to make sense of the natural world. Engaging in these practices not only provides students with a deeper understanding of the process by which scientific knowledge is formed and refined over time but also encourages them to actively partake in the construction of their own knowledge.12 Unfortunately, it can be very difficult and timeconsuming to develop these types of laboratory experiences. Additionally, while the K−12 community has made significant strides toward developing curriculum that integrates the three

aboratory experiences have the ability to provide students with opportunities to engage in scientific practices in a way that reflects how scientists actually work within their professions.1−3 Unfortunately, many traditional laboratory curricula do not take advantage of the great potential of these experiences.4−7 As a result, recent education reform has called for school science to better mirror authentic scientific endeavors. It is thought that by engaging fully in scientific practices within a discipline, students will better understand the field’s epistemic basis and thus be able to later become contributing members to the field.8 In response to this call for reform at the K−12 level, curriculum models such as the National Research Council’s Framework for K−12 Science Education and the Next Generation Science Standards (NGSS) have been developed.9,10 The goals of these models are to enhance student learning by focusing on three dimensions: crosscutting concepts, disciplinary core ideas, and scientific and engineering practices. To develop well-trained scientists, students should participate in course experiences where these three dimensions are integrated together within the curriculum both in the tasks students complete and in the assessments related to those tasks.11 The idea of science as a set of practices stems from the perspective that science includes specialized ways of talking, © XXXX American Chemical Society and Division of Chemical Education, Inc.

Received: January 7, 2019 Revised: July 2, 2019

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DOI: 10.1021/acs.jchemed.9b00008 J. Chem. Educ. XXXX, XXX, XXX−XXX

Journal of Chemical Education

Laboratory Experiment

Figure 1. Schematic overview of the cross-course collaborations involved in the biodiesel experience.

Learning Outcomes section). The results of this evaluation were combined with a literature review of best practices for student work in chemistry laboratories,9,18−23 various content standards (core ideas24,25), scientific practices,11 institution and departmental requirements, and the instructors’ goals for student learning. The result was the development of five learning goals that students should obtain after having completed the laboratory course; that scientists must: (1) Define problems and develop plans/carry out investigations to solve those problems. (2) Collaborate with other scientists and build on previous work. (3) Use chemistry content and laboratory skills effectively to solve problems. (4) Communicate results with one another and other nonscientists at an appropriate scientific level. (5) Do the previous four both ethically and safely. From these learning goals, a set of detailed learning objectives at the biodiesel laboratory experience level was developed for each course involved in the experience. These objectives mapped onto the course, department, and institutional learning goals and objectives (course level learning objectives can be found in Supporting Information section B.2). Care was taken to write objectives that had an observable, measurable action verb and were not too complex (and thus could be measured using one assessment instrument). Once these learning objectives were written, acceptable evidence of student learning was identified for each objective. This evidence was then used to create grading rubrics or content tasks, such as prelaboratory quizzes, to be used as assessment instruments. Finally, once the learning objectives, acceptable evidence, and evaluation materials had been identified, the laboratory experience itself was developed.

dimensions, the undergraduate community has not come nearly as far. This is evidenced by the limited number of experiences published by the Journal, which meet these criteria.13−15 Many more laboratory exercises that focus on crosscutting concepts, disciplinary core ideas, and scientific and engineering practices are needed so that an instructor or department can implement a full curriculum. This paper presents a multiweek, multicourse biodiesel laboratory experience that was developed using a backward design model to intentionally cover specific chemistry content and laboratory skills.16 This experience provides vertically scaffolded learning experiences for students to develop skills with a focus on scientific practices.

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BACKWARD DESIGN

Identifying Desired Results

This laboratory experience was designed through a backward design curricular reform model where the desired results and assessment methods were identified prior to the development of the laboratory procedures.16 This method of curricular reform along with a transparent teaching philosophy results in an intentionally designed, well-defined laboratory experience where both the instructor and the students are aware of three things: (1) the purpose of each task within the laboratory experience, (2) a detailed description of each task, and (3) how each task will be assessed.17 The first step in this backward design process was the identification of desired results. This was an intensive multistep process that began with the collection of two years of baseline data to determine what was happening in the previous curriculum. The data collected included laboratory observations, products of student work, student interviews, and the use of the 3DLAP.11 This in-depth evaluation showed exactly how students were spending their time in the laboratory curriculum and what holes were present in terms of both conceptual and skill acquisition (see results of this analysis in the Student

Biodiesel

A biodiesel laboratory experience was selected to address the identified learning objectives for multiple reasons. First, the B




chemistry students; alternatively, samples could be evaluated using gas chromatography/mass spectrometry (GC/MS) techniques if access to NMR spectrometers is not available. Usually the quality of the general chemistry samples is found to be such that a purification method would be beneficial. The general chemistry students are instructed on how to locate literature on purification methods and apply them to their samples. In the meantime, the organic chemistry students are self-designing studies to determine the optimal conditions for their microwave transesterification that will result in a method that is cognizant not only of the effectiveness of biodiesel production but also the amount of waste produced and the environmental impact of this method, all of which they will later report to the general chemistry students. Finally, the efficiency of the two methods (traditional vs microwave) and the properties of the biodiesel are investigated. The organic chemistry students evaluate the efficiency by comparing NMR (or GC/MS) spectra of the final samples. The general chemistry students synthesize this information in a response letter to the parks department, and then all students in each course separately write formal laboratory reports detailing the experience. There is a large focus on within-class and between-class collaboration during this experience. The general chemistry students receive the initial call to action, but the rest of the classes are brought into the experience upon the request of the general chemistry students. This puts the upper-division students into place as collaborators with specific requested expertise (ability to analyze samples via NMR, perform microwave transesterification, perform bomb calorimetry, etc.). Within classes, the students must work together often to identify the best possible results. A collaboration plan and reflection document in which students identify the day’s goals, the tasks that will be completed by each member, how the day went, and when they will meet in the intervening week is completed at the beginning and end of each general and organic chemistry laboratory (though this process, including how it is graded, looks different for the two courses). This process has been used in other laboratories reported in the Journal and helps to facilitate effective collaboration between partners.13 During the various collaborations, students communicate with one another via the letters shown in Figure 1. If additional communications beyond the letter are necessary, instructors facilitate them happening via a shared electronic folder. In most cases, the request for collaboration and reporting letters are sufficient for the needs of this laboratory experience. Any compilation of data was done via a shared online document accessible to all students. For example, students uploaded their biodiesel NMR results to a shared document before a specified deadline. At the deadline, all students could then use the compiled data to draw conclusions. Finally, a group logistics document was created to facilitate the collaborations required for this large scale group work (found in the Supporting Information Section B.4). This level of cross-course collaboration requires a dedicated level of instructor-level facilitation and open lines of communications both between sections of a course as well as between the various courses. Weekly instructor/TA meetings, course and experience-level coordinators, common assignment descriptions and grading rubrics, and use of shared electronic assignment submission systems are recommended to ensure a unified and consistent experience for the students (these

department had previously utilized various iterations of biodiesel laboratories and was thus familiar with the content and equipment setup that the procedures required. In fact, all levels of laboratory procedures in the biodiesel laboratory experience, with the exception of the self-designed portion in the organic chemistry laboratory, were implemented multiple times within the department’s curriculum before they were brought together into this scaffolded experience. Second, the biodiesel laboratory’s applications to the world outside the institution aligned nicely with the college’s mission, vision, and values statement, which include the promotion of environmental stewardship and social responsibility.26 Finally, the many factors that go into the creation of biodiesel have been reported extensively in the literature.27−29 Indeed, there were a number of biodiesel laboratory components already published in the Journal that could be used to create the laboratory experience intentionally aimed at the stated learning objectives.28,30−32 For these reasons, the biodiesel topic was selected as the context for creating the laboratory experience.

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BIODIESEL LABORATORY EXPERIENCE DETAILS

Laboratory Procedures and Timeline

A detailed description of the laboratory experience, broken down into each course, by week, along with a proposed timeline for the experience can be found in the Supporting Information (Section B). The timeline details the weeks of the experience starting with the beginning of the experience as week 1 (though this may not be the first week of the semester depending on the program). The general chemistry course starts on week 1 with the other courses starting only after they have been called to action by the general chemistry students. It should also be noted that while this experience is a major component of the general and organic chemistry curriculum, it plays a smaller role in the physical chemistry course. Therefore, the description here and the Supporting Information focus on the general and organic chemistry experience (though materials are also provided for the physical chemistry components). The majority of the general chemistry procedures are based off of three sources,27−29 though later in the experience students are required to locate additional resources. The novelty of the experience described here is in the combination of these previously described procedures in a scaffolded biodiesel laboratory experience that mimics the practice of science by including a heavy emphasis on collaboration, writing, and student-designed components. The overview of the laboratory is represented in Figure 1 and can be described as follows: the general chemistry students are contacted by the National Parks Department and tasked with developing an effective, low-cost, and environmentallyfriendly method for developing biodiesel through the transesterification of vegetable oil.25 The general chemistry students then call on both the organic and physical chemistry students to assist them in this request. Both the general and organic chemistry students develop biodiesel through different methods. The organic chemistry students synthesize their biodiesel using a microwave transesterification method and a CaO catalyst previously prepared for them by the general chemistry students.27 The general chemistry students synthesize their biodiesel sample using a more traditional alkaline catalyst and transesterification method.29 The organic chemistry students then evaluate the quality of both groups’ samples by NMR and send this evaluation to the general C




procedures making quality performance much more important for the success of the laboratory. All procedures that ultimately came together to synthesize the biodiesel laboratory experience were previously used in the department’s various laboratory curricula. The creation of the CaO catalyst (general chemistry) was utilized three semesters with roughly 200 students participating; the creation of biodiesel using an alkaline catalyst and testing its viscosity (general chemistry) was utilized eight semesters with roughly 500 students; the creation of biodiesel using the CaO catalyst and microwave transesterification method was utilized two semesters with roughly 100 students; finally, the combination of the biodiesel laboratory experience as is presented here has been utilized three times, once as a pilot with around 25 students, and twice fully implemented with 241 students (number reflects general (137), organic (86), and physical (18) chemistry students compiled).

recommendations are detailed in the Supporting Information Section D.1). Throughout the experience, students build their skills in finding scientific literature, effectively reading and evaluating that literature, and using it as their background information to create experimental procedures. These skills are scaffolded throughout the experience both within a single course and between courses. For example, in week 1, the general chemistry students read through a provided journal article26 along with their instructor. Together as a class they identify the components necessary to replicate the creation of CaO detailed in the paper. In the second week, students are provided a paper on different transesterification methods and use the information from the paper to create procedures with their partners.29 Next, the students determine they need a purification process for their biodiesel samples. After a tutorial session on key-term searches, the students are required to locate their own peer-reviewed journal article, which they must then use to create their own procedures. In the final week, the general chemistry students are tasked again to find their own procedures for testing biodiesel viscosity. This often requires them to evaluate the reliability of sources other than peerreviewed journal articles as published papers on viscosity of fuels are difficult to locate. This scaffolded progression provides students with opportunities to build on their skills as they move from 1 week to the next. The scaffolding is also present from course to course where upper-division students are expected to function at a higher level on each of these skills then the introductory students. There is also a large focus on written communication of scientific findings. In all classes, the students have two forms of scientific communications: (1) a formal report which follows scientific conventions and on which they receive intensive feedback, and (2) a letter with a stakeholder who has less chemical knowledge then they themselves have (general chemistry with the national parks department, organic chemistry with general chemistry, and physical chemistry with general chemistry). Through this process, students develop the communication skills of engaging in argument from evidence and communicating their findings to audiences with varying levels of scientific backgrounds. The full biodiesel laboratory experience was designed so that as a student progresses through their chemistry coursework, they will encounter this topic at multiple levels of the curriculum. This approach, where students’ engagements with experiences are connected over time and do not take the form of a “one off” experience, has been shown to be a necessary component of coherent, integrated, and intentional curriculums.33 This repetition not only reinforces the chemistry content but also allows the students to recognize how their understanding of both the content and their skills as practicing scientists grow. Working with students from other classes better reflects collaborations in the workforce where different colleagues bring different expertise to the table. Each collaborator must trust their colleagues to perform their portion of the experiment but must also educate themselves well enough in what their colleagues are doing so they may contribute to the conversation and evaluate the quality of the work. Another result of this in-depth collaboration is the expectation that students feel an increased sense of ownership in their work as they are sending their products to other students who will then use them to complete their own

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HAZARDS Students are required to wear safety goggles and protective equipment throughout the laboratory experience. Students are also required to read and summarize the MSDS data in a table format. All of the reagents and solvents should be considered hazardous or irritating upon contact or inhalation. The organic solvents used are potential fire hazards. All of the waste disposal should be done in compliance with local requirements.

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STUDENT OUTCOMES All data presented in this section were collected after securing IRB approval (St. Mary’s IRB documents SP14_38, SP15_40, SP16_32, and SP17_67). A full description of each week’s procedures for the three courses and the products created is included in the biodiesel laboratory description of experience (Section B.1), student instructions (Section C), and faculty instructions (Section D), found in the Supporting Information. Experimental Outcomes

General Chemistry. In the general chemistry laboratory, students first synthesize a CaO catalyst, which will later be sent to the organic students. Students often fail to make pure CaO on their first attempt even if they follow the procedures outlined in Wei et al.27 This is due to temperatures that are too low, too short of a duration in the muffle furnace, or due to temperature gradients within the muffle furnace (hot and cold points). They can identify their failure to synthesize pure CaO through various methods such as weighing the samples (conservation of mass), checking for color and consistency of the product, or reacting it with 10% HCl(aq). Figure 2 shows the difference between eggshells that have and have not been completely converted to CaO. This failure to produce the desired product creates an excellent opportunity for students to practice “real science” where they must alter their procedures the following week in response to unexpected results. After they successfully synthesize their pure CaO catalyst, they are taught how to properly label and seal their sample by closing the top of the vial and covering it in parafilm to prevent exposure to oxygen. Finally, they send their samples to the organic students for use in the microwave transesterification process. In the second week, the general chemistry students use a paper by Meher et al.29 to create procedures for a transesterification process using traditional cooking methods D




variation in procedures within a class. A sample NMR of the biodiesel created from these methods is included in Figure 3. Interpretation of the output is relatively simple. At the authors’ institution, the undergraduate organic teaching assistants give a short PowerPoint presentation instructing the general chemistry students in the process. If the α carbon peak integration found at 2.3 ppm is set to two, then the methyl/ethyl ester group peak found between 3.6 and 3.7 ppm should integrate to three if there was 100% conversion. The students can simply divide the number found for their peak (created for them by the organic chemistry students) by three to get a rough estimate of their percent conversion. In the eight semesters reported, the range of conversion from vegetable oil to biodiesel has generally been between 80 and 95% according to NMR analysis. Once the students receive their NMR analysis with instructions on how to interpret them, most groups determine they would like to further purify their sample. After some key-term search instruction, students locate their own purification procedures keeping in consideration the cost and environmental impact of their methods. This leads most students either to a water or silica wash method. After this wash, most groups increase the purity of their sample around 3−5%. It should be noted that groups who use a water wash run the risk of creating an emulsion. Instructors can decide whether to warn their students about this. If an emulsion is created, it provides yet another opportunity for students to find and use procedures to “break” the emulsion. Finally, students are charged with finding procedures to test the viscosity of their samples. Many methods exist that do not require specialized equipment, though viscometers may be used if available. Students then calculate the viscosity of their biodiesel sample and compare it to that of other fuels, often in table format. An example table of student results has been included in the Supporting Information (Section C.2). In the eight semesters this procedure was utilized, students consistently obtained viscosities around or just above that of regular gasoline (0.005−0.006 Poise). Organic Chemistry. The organic chemistry students are invited to collaborate by the general chemistry students who also provide the needed background information for the collaboration request. The organic chemistry students use the CaO catalyst to synthesize biodiesel from vegetable oil via a microwave transesterification method. The biodiesel produced by this method typically gives close to 100% biodiesel. A

Figure 2. (a) Eggshell partially converted to CaO (left) versus fully converted (right). Note the similar appearance in the crucible. (b) Eggshell poured onto a watch glass. Note the difference in colors between partially and fully converted samples. (c) Sample from a and b reacted with 10% HCl. Note the partially converted sample produces CO2 gas, while the fully converted sample does not.

and an alkaline catalyst. After reading the paper, students will not all create the same procedures as there is no definitive “best method” outlined by this review paper, only general guidelines. This creates a good amount of “controlled”

Figure 3. Sample NMR from general chemistry students’ creation of biodiesel using traditional catalyst and methods. Note that integrations have been normalized such that the peak at 2.3 ppm is exactly 2.00 ppm. E




Figure 4. Sample NMR from organic chemistry students’ creation of biodiesel using CaO catalyst and microwave methods. Note that integrations have been normalized such that the peak at 2.3 ppm is exactly 2.00 ppm.

sample NMR of the synthesized biodiesel is included in Figure 4. Students then go on to research and create their own methods to optimize this process while keeping waste and environmental impact in consideration. They do this by altering different variables in the transesterification process (cook time, temperature, etc.) and seeing how they affect the product by measuring percent conversion, impurities, etc. For example, if student use time as the independent variable, they will find that shorter reaction times result in less than 100% conversion. Students generally find that microwaving samples for 20 min at 120 °C is an effective reaction time and generally discover that reducing catalyst loadings to 50% of their original values provides equally pure biodiesel. When investigating other alcohols, they see that some carboxylic acid is formed when using ethanol versus methanol likely due the ethanol used, which is purchased in larger stock quantities and at lower purities for cost savings. When reusing the recovered catalyst, students see a substantial decrease in conversion to biodiesel. Using microwave radiation for the synthesis procedures saves a great amount of time, which then allows the students to try a number of different procedures and determine which works best. The organic chemistry students are responsible for acquiring NMR of their own and the general chemistry students’ biodiesel samples and then report the findings back to the general chemistry students. Physical Chemistry. The physical chemistry students are invited into the collaboration by the general chemistry students and asked to take the biodiesel synthesized and test it for energy output using bomb calorimetry. The physical chemistry students learn the concepts associated with bomb calorimetry in the first semester of the course. During the biodiesel laboratory experience (which occurs in the second semester), the physical chemistry students are asked to develop a literature-based hypothesis regarding the energetics of biodiesel that allows them to involve the general chemistryproduced samples in their study. To help facilitate the physical chemistry learning objectives (see Supporting Information Section B.2 for a detailed list of these objectives), students are asked to complete their own search of the literature to (1) determine the fatty acid composition of soybean oil and use that information to calculate a molar mass for soybean oil; (2) look in the literature to determine the types of modifications diesel engines require to run on pure biodiesel; and (3) locate

and write out the transesterification reaction that the general chemistry students performed. Tasks (1) and (3) are critical to understanding/recalling the chemistry performed by the general chemistry students and to calculating the energy released by unreacted oil and the biodiesel samples on a molar basis. Since the general chemistry students are measuring the viscosity at the same time and therefore not transmitting that data, task (2) provides the physical chemists with a context for understanding the advantages and limitations of biodiesel for their letters, presentations, and forming a literature-based hypothesis. In the laboratory, each group will perform at least one bomb calorimetry experiment with a standard sample to verify their calorimeter heat capacity constant. Only one trial is needed in general since the collaborating physical chemistry students were required to calibrate the bomb calorimeters using multiple measurements on the same standard in a prerequisite course the previous semester. Each laboratory group then begins testing fuel samples. Typically, students are provided petroleum-derived diesel fuel, the general chemistry biodiesel samples, and several unreacted vegetable oils available in the laboratory, though other fuels may be obtained as needed. Ideally, the partner groups perform multiple trials of each sample or pool data so that they can test more samples while providing some estimate of the uncertainty in the data they acquire. This process generally takes 2 weeks of laboratory time. Each group prepares a formal letter summarizing their findings that are delivered to the general chemistry students. In addition, the group leader will have to present their findings formally to the physical chemistry II laboratory class, a standard feature of the physical chemistry laboratory sequence. Student Learning Outcomes

Learning Outcomes in Individual Courses. To evaluate students’ performance on content understanding, basic laboratory skills, and scientific practices, various grading rubrics or content tasks were utilized. Data presented here are for the spring 2017 and 2018 semesters as those students were the first cohorts to complete the full biodiesel experience. Time and space do not allow the authors to report on each individual learning objective. Instead, the learning objective scores have been combined into five overarching categories that align with the original five learning goals identified for the course: (1) defining problems and developing a plan to investigate these problems; (2) collaboration; (3) laboratory skills and chemistry content; (4) communication; and (5) F




Figure 5. Histograms of scores for the general and organic chemistry courses on each of the five stated learning goals. Note that the scale of the y axis is different for each course due to the different number of students and the axis in goal #5 for the organic course is different to accommodate the large number of students found in one category. A detailed description of which assignments and point values are combined into each category can be found in the Supporting Information Section A.2.

ethics/safety. Histograms for students’ combined scores in each of these categories for the general and organic chemistry classes are provided in Figure 5. A detailed description of which assignments and point values are combined into each category can be found in the Supporting Information Section A.2. The data show that most students perform at or above a 70% with a majority consistently performing above 80% within each category. This indicates that students are meeting the five learning goals after completing the biodiesel laboratory experience. The physical chemistry assignments focused on students developing procedures and corresponding with the general chemistry students. Analysis of students’ scores on related assignments resulted in similar trends as seen in Figure 5 with most students scoring above a 70% and thus meeting the physical chemistry related learning objectives. Learning Experience as a Whole. Trained field observers conducted laboratory observations to examine student behaviors during the biodiesel laboratories. For each organic

laboratory section observed, data were collected using a behavior checklist and through brief interviews with laboratory groups throughout the laboratory period. Laboratory observations were conducted for the entire laboratory period using 5 min intervals with each laboratory group (2 min for direct observation, 2 min for interview questions, and 1 min for summary note-taking). For each general chemistry section, only the behavior checklist was used without the interview portion (4 min for direct observation and 1 min for summary note-taking). During each of the laboratory classes, the field observer rotated among the laboratory groups, observing a new group every 5 min, repeating the rotation as needed to span the entire length of the laboratory period. The checklist of behaviors was identified through an extensive literature review and was adapted from the Inquiring into science instruction observation protocol (ISIOP).34 The observation protocol identified behaviors in six categories: (1) developing questions and hypothesis; (2) designing investigations; (3) data collection and organization; G




Table 1. Comparison of Student Time Expended on Various Categories of Laboratory Behaviors Laboratory Behaviors

Student Time Spent by Course on Select Laboratory Behaviors, % Organic Chemistry Course

1 2 3 4 5 6

Generating questions/hypotheses Designing investigations Collecting and organizing data Analyzing data Evaluating results and communicating them General academic behaviors

General Chemistry Course

Traditional (N = 58)

Biodiesel (N = 43)

Traditional (N = 77)

Biodiesel (N = 74)

0.0 0.3 74.4 3.1 0.0 22.2

0.3 2.5 70.2 6.7 1.1 19.2

0.0 0.0 83.1 5.7 0.0 11.2

0.2 11.0 62.1 8.1 10.6 8.0

Figure 6. Assessment of the biodiesel laboratory experience components using 3DLAP.11 A colored box indicates that this dimension was characterized as being present in the biodiesel laboratory experience by meeting all of the stated criteria for that category. The three colors represent the three dimensions of the learning assessment protocol (blue = scientific practices, green = crosscutting concepts, and red = core ideas).

(4) analysis; (5) evaluation and communication; and (6) general academic behaviors. When compared to traditional, often confirmatory laboratory exercises (either previous iterations of the biodiesel experience or other laboratories that had not been intentionally developed using the backward design model), the laboratory observation data show two findings. First, the new type of laboratory experience results in an increase in the variety of behaviors exhibited by students. This can be seen in Table 1 through the increase percentage in the behavior categories developing questions and hypothesis, designing investigations, analysis, and evaluation and communication. This is especially apparent in the general chemistry course, which transitioned from a purely confirmatory biodiesel exercise to the current model (versus organic chemistry which had already started utilizing some best practices in those exercises identified as “traditional”). Second, there is a general decrease in the percent of time on data collection and organization, and general academic behaviors. This indicates a decrease both in the behaviors most associated with confirmatory exercises (data collection and organization) as well as off-task behavior. Together, these data seem to indicate that the biodiesel experience results in students spending more time engaging in scientific practices. In addition to the laboratory observations detailed above, the overall biodiesel experience was also characterized using the three-dimensional learning assessment protocol (3DLAP) to evaluate whether the experience provided learning

opportunities for the students within the three dimensions identified as requisite in science courses: scientific and engineering practices, crosscutting concepts, and disciplinary core ideas.11 To characterize the presence of these three dimensions within the biodiesel experience, the following artifacts were evaluated: assignment descriptions (Supporting Information Sections B.1 and C.3), prelab instructions (Sections B.1 and C.2), and grading rubrics (Section C.4). In Figure 6, a box was filled in when the scientific practice, crosscutting concept, or core idea was located within at least one of the artifacts for all three courses. For example, the scientific practice “Planning Investigations” is included as present because the requisite criteria were identified in the assignment descriptions and grading rubrics for general, organic, and physical chemistry. The results of this analysis indicate that the biodiesel experience supports the development of students in at least two categories within all three dimensions and thus provides an experience that mimics that of a scientist working within their scientific discipline.

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FUTURE WORK In addition to the future changes in response to student learning data described above, the authors also plan to include additional connections to upper-division classes as well as to campus applications of the synthesized biodiesel. Additional connections to physical chemistry content and connections to quantitative analysis or instrumental analysis courses are possible and are being investigated. The tasks in these courses H




may include further analysis of the CaO or biodiesel samples for purity.35,36 The authors have also started to work with the college to determine the potential of using vegetable oil waste from the school kitchens and converting it to biodiesel on a large enough scale so that it can be used to power a campus vehicle. The authors feel that the connections possible with other courses (either chemistry or other departments) and campus applications are only limited by the context of the institution at which this experience is implemented.

Geoffrey M. Bowers: 0000-0003-4876-9305 Daniel T. Chase: 0000-0002-4957-0261 Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS The authors would like to thank the many instructors involved in creating and implementing this laboratory experience. We would also like to thank Elan Bresslour-Rashap, Leslie Malick, and Meredith McKissick, undergraduate students who performed much of the background research on the methods and procedures ultimately used. Finally, we would like to thank Allison M. Burnett for photographing the eggshell catalyst and biodiesel samples. The development of this laboratory experience was supported by the National Science Foundation (NSF-DUE Award Nos. 1323025 and 1625354).

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LIMITATIONS A few possible limitations of this experience have been identified by the authors. One limitation could be the logistics involved in implementing this at a large institution, which would be much more difficult in terms of sharing samples between sections. In this case, the authors suggest combining samples within each section into one “master” sample that is shared with collaborators. Thus, sample sharing would be much more simplified and easier at a larger scale. A second limitation could be an institution not having access to an NMR spectrometer or the amount of time the instrument can be dedicated to a teaching laboratory. Sample NMR spectra have been provided in the Supporting Information Section D.3 so that these spectra can be used by courses rather than having the students acquire them themselves. Also, if instrument use time is limited, the samples in a section could be combined into one “master” sample rather than having each individual group analyze a sample. Finally, GC/MS could be an alternative testing method to NMR. Another limitation of this experience could be the use of a microwave for the transesterification in the organic chemistry courses. If no microwave is available, the organic students may not be able to easily self-design methodology as traditional synthesis methods take much longer than using the microwave. In this case, having the general chemistry students collaborate with students in a quantitative or instrumental analysis course may take the place of the organic student collaborations. A final limitation to utilizing this experience is the amount of time necessary. If this is the case, the authors suggest cutting certain portions of the experience. For example, the general chemistry students need not complete the purification portion if time is a concern. The students could instead be instructed on how to locate purification methods and propose them to the Parks Department rather than actually perform the purification.

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(1) Hofstein, A.; Lunetta, V. N. The Role of the Laboratory in Science Teaching: Neglected Aspects of Research. Rev. Educ. Res. 1982, 52 (2), 201−217. (2) Hodson, D. Laboratory Work as Scientific Method: Three Decades of Confusion and Distortion. J. Curr. Stu. 1996, 28 (2), 115− 135. (3) Tobin, K. Research on Science Laboratory Activities: In Pursuit of Better Questions and Answers to Improve Learning. Sch. Sci. Math. 1990, 90 (5), 403−418. (4) Sandi-Urena, S.; Cooper, M. M.; Gatlin, T. A.; Bhattacharyya, G. Students’ Experience in a General Chemistry Cooperative Problem Based Laboratory. Chem. Educ. Res. Pract. 2011, 12 (4), 434−442. (5) Gabel, D. Improving Teaching and Learning through Chemistry Education Research: A Look to the Future. J. Chem. Educ. 1999, 76 (4), 548. (6) Hart, C.; Mulhall, P.; Berry, A.; Loughran, J.; Gunstone, R. What is the Purpose of this Experiment? Or Can Students Learn Something from Doing Experiments? J. Res. Sci. Teach. 2000, 37 (7), 655−675. (7) Hofstein, A.; Mamlok-Naaman, R. The Laboratory in Science Education: the State of the Art. Chem. Educ. Res. Pract. 2007, 8 (2), 105−107. (8) Duschl, R. A.; Grandy, R. Two Views About Explicitly Teaching Nature of Science. Sci. & Educ 2013, 22 (9), 2109−2139. (9) A Framework for K−12 Science Education: Practices, Crosscutting Concepts, and Core Ideas. National Research Council; National Academies Press: Washington D.C., 2012. (10) Achieve. Next Generation Science Standards; National Research Council: Washington, D.C., 2013. http://www.nextgenscience.org/ (accessed July 2, 2019). (11) Laverty, J. T.; Underwood, S. M.; Matz, R. L.; Posey, L. A.; Carmel, J. H.; Cabellero, M. D.; et al. Characterizing College Science Assessments: The Three-Dimensional Learning Assessment Protocol. PLoS One 2016, 11 (9), No. e0162333. (12) Osborne, J. Scientific Practices and Inquiry in the Science Classroom. In Handbook of Research on Science Education; Lederman, N. G., Abell, S. K., Eds.; Routledge: New York, NY, 2014; Vol. 2, pp 579−599. (13) Carmel, J. H.; Ward, J. S.; Cooper, M. M. A Glowing Recommendation: A Project-Based Cooperative Laboratory Activity To Promote Use of the Scientific and Engineering Practices. J. Chem. Educ. 2017, 94 (5), 626−631. (14) Keller, V. A.; Kendall, B. L. Independent Synthesis Projects in the Organic Chemistry Teaching Laboratories: Bridging the Gap Between Student and Researcher. J. Chem. Educ. 2017, 94 (10), 1450−1457. (15) Pagano, J. K.; Jaworski, L.; Lopatto, D.; Waterman, R. An Inorganic Chemistry Laboratory Course as Research. J. Chem. Educ. 2018, 95 (9), 1520−1525.

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S Supporting Information *

The Supporting Information is available on the ACS Publications website at DOI: 10.1021/acs.jchemed.9b00008. Manuscript related documents (PDF, DOCX) Curricular documents (PDF, DOCX) Student facing documents (PDF, DOCX) Instructor facing information and documents (PDF, DOCX)

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REFERENCES

AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. ORCID

Kelly Y. Neiles: 0000-0002-5586-4389 I




(16) Wiggins, F.; McTighe, J. Understanding by Design, 2nd ed.; Association for Supervision and Curriculum Development: Alexandria, VA, 2005. (17) Winkelmes, M.; Bernacki, M.; Butler, J.; Zochowski, M.; Golanics, J.; Weavil, K. H. A Teaching Intervention that Increases Underserved College Students’ Success; Association of American Colleges & Universities, 2016; Vol. 18 (1/2). (18) Abraham, M. R. What Can be Learned from Laboratory Activities? Revisiting 32 Years of Research. J. Chem. Educ. 2011, 88 (8), 1020−1025. (19) Vision and Change in Undergraduate Biology Education: A Call to Action; American Association for the Advancement of Science, 2011. (20) Domin, D. S. A Content Analysis of General Chemistry Laboratory Manuals for Evidence of Higher-Order Cognitive Tasks. J. Chem. Educ. 1999, 76 (1), 109. (21) Domin, D. S. Considering Laboratory Instruction through Kuhn’s View of the Nature of Science. J. Chem. Educ. 2009, 86 (3), 274. (22) Jensen, J. L.; Lawson, A. Effect of Collaborative Group Composition and Inquiry Instruction on Reasoning Gains and Achievement in Undergraduate Biology. CBE Life Sci. Educ. 2011, 10 (1), 64−73. (23) Naiker, M.; Wakeling, L. Evaluation of Group Based Inquiry Oriented Learning in Undergraduate Chemistry Practicals. Int. J. Innov. Sci. Math. Educ. 2016, 23 (5), 1−17. (24) Cooper, M. M.; Posey, L. A.; Underwood, S. M. Core Ideas and Topics: Building Up or Drilling Down? J. Chem. Educ. 2017, 94 (5), 541−548. (25) Undergraduate Professional Education in Chemistry: ACS Guidelines and Evaluation Procedures for Bachelor’s Degree Programs; American Chemistry Society: Washington, D.C., 2015. (26) St. Mary’s College of Maryland, Mission and Values; St. Mary’s College of Maryland, 2019. http://www.smcm.edu/about/mission/ (accessed July 2, 2019). (27) Wei, Z.; Xu, C.; Li, B. Application of Waste Eggshell as LowCost Solid Catalyst for Biodiesel Production. Bioresour. Technol. 2009, 100, 2883−2885. (28) Clarke, N. R.; Casey, J. P.; Brown, E. D.; Oneyma, E.; Donaghy, K. J. Preparation and Viscosity of Biodiesel from New and Used Vegetable Oil. An Inquiry-Based Environmental Chemistry Laboratory. J. Chem. Educ. 2006, 83 (2), 257. (29) Meher, L. C.; Vidya Sagar, D.; Naik, S. N. Technical Aspects of Biodiesel Production by Transesterification − A Review. Renewable Sustainable Energy Rev. 2006, 10, 248−268. (30) Pohl, N. L.; Streff, J. M.; Brokman, S. Evaluating Sustainability: Soap versus Biodiesel Production from Plan Oils. J. Chem. Educ. 2012, 89 (9), 1053−1056. (31) Bladt, D.; Murray, S.; Gitch, B.; Trout, H.; Liberko, C. AcidCatalyzed Preparation of Biodiesel from Waste Vegetable Oil: An Experiment for the Undergraduate Organic Chemistry Laboratory. J. Chem. Educ. 2011, 88 (2), 201−203. (32) Bucholtz, E. C. Biodiesel Synthesis and Evaluation: An Organic Chemistry Experiment. J. Chem. Educ. 2007, 84 (2), 296. (33) Finley, A. Evidence and Other Eight-Letter Words: Musings from the National Evaluator (Winter 2016 Newsletter); Bringing Theory to Practice, 2016. http://www.bttop.org/news-events/evidence-andother-eight-letter-words-musings-national-evaluator (accessed July 2, 2019). (34) Minner, D.; DeLisi, J. Inquiring into Science Instruction Observation Protocol (ISIOP); Education Development Center: Waltham, MA, 2012. (35) Ault, A. P.; Pomeroy, R. Quantitative Investigations of Biodiesel Fuel Using Infrared Spectroscopy: An Instrumental Analysis Experiment for Undergraduate Chemistry Students. J. Chem. Educ. 2012, 89 (2), 243−247. (36) Knoerzer, T. A.; Hill, E. M.; Davis, T. A.; Iacono, S. T.; Johnson, J. E.; Balaich, G. J. Comparative Analysis of Fuel Composition and Physical Properties of Biodiesel, Diesel, Kerosene, and Jet Fuel. J. Chem. Educ. 2018, 95 (10), 1821−1826. J


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