Purposeful Design of Formal Laboratory Instruction as a

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Purposeful Design of Formal Laboratory Instruction as a Springboard to Research Participation David P. Cartrette* and Matthew L. Miller Department of Chemistry and Biochemistry, South Dakota State University, Brookings, South Dakota 57007, United States S Supporting Information *

ABSTRACT: An innovative first- and second-year laboratory course sequence is described. The goal of the instructional model is to introduce chemistry and biochemistry majors to the process of research participation earlier in their academic training. To achieve that goal, the instructional model incorporates significant hands-on experiences with chemical instrumentation, beginning in the first semester and continuing through the fourth semester. The model also strives to instill within students an understanding of the social aspects of a working research laboratory, where members enter and gradually change roles based on increased experience and responsibility. An implicit assumption in the instructional model is that students gradually move from verification experiences to more open-inquiry experiences, which mimics the process of joining a working research laboratory. The capstone experience in this model is a laboratory stand-alone course, where students design and implement experiments related to faculty research projects within the department. Ideas for broader implementation of the model at various types of institutions are also suggested. A paper describing the implementation of the model is forthcoming. KEYWORDS: First-Year Undergraduate/General, Second-Year Undergraduate, Curriculum, Laboratory Instruction, Organic Chemistry, Physical Chemistry, Collaborative/Cooperative Learning, Hands-On Learning/Manipulatives, Inquiry-Based/Discovery Learning, Undergraduate Research

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listing of the available tools, suggested experimental procedures, and hints to the outcomes of these procedures. In guidedinquiry exercises, the onus of scientific work is placed directly on the student, such that they become scientists in training rather than laboratory technicians. Another innovation in laboratory curriculum efforts has been to introduce students to advanced instrumentation early in the degree program.18−20 In typical undergraduate chemistry programs, students often are not introduced to sophisticated instrumentation until the third or fourth year in the degree track, if at all in some cases. The premise of a prior federally funded laboratory teaching program was that students acquire a better appreciation and understanding of instrumentation if they were exposed to that instrumentation at multiple times during the undergraduate program. Evaluative outcomes of that program showed that students, when given the opportunity to work with more advanced instrumentation (e.g., HPLC and CE), left the course with an enhanced understanding of these techniques.18−20 An additional outcome of these studies described students as being more confident in their use of the instrumentation and being empowered to utilize the instrumentation in future experiments. Here, we describe an innovative approach to the first- and second-year laboratory curriculum for chemistry and biochemistry majors. The chemistry and biochemistry department reviewed its undergraduate curriculum two years ago, informed by two factors: an institutional program review (IPR) and changes to curriculum standards issued by the Committee for Professional Training (CPT) of the American Chemical Society (ACS). The IPR recommended that the department invest

he drive for curriculum improvement in STEM disciplines is not new1−3 and is a constantly evolving process dedicated to better science education for U.S. citizens. Calls for reform speak to several pertinent issues specifically related to science education: to provide authentic opportunities for students to experience science experimentation as scientists do;4−6 to increase the competitiveness of future generations of the U.S. scientific workforce;7 to enhance the conceptual understanding of students in scientific disciplines;8,9 and to foster a sense of applicability and critical thinking among students.10,11 Several laboratory curriculum innovations have been tested, with varying degrees of reported success in the literature. One example is the use of inquiry-based laboratory instruction.10,11 The premise of the inquiry laboratory experience is to give students a better idea of the planning, execution, and evaluation of results of an experiment; the ultimate goal is to provide students with a “real-life” experience, much like that which a practicing scientist experiences on a daily basis in his or her normal workday. Literature summaries of the influences of such a curriculum generally reach positive conclusions: in some studies, students attain higher laboratory skill,12 and in some students were reported to attain greater conceptual understanding.12,13 The use of blended or integrated laboratory exercises has also been reported in the literature.14−16 The blended or integrated laboratory exercise is intended to apply principles from several concepts toward one solvable problem in either one or several laboratory periods. One trait of these integrated laboratory experiences is the level of inquiry involved in them; most examples reported in the literature rely on guided inquiry.17 In other words, students are given a problem description and a © 2013 American Chemical Society and Division of Chemical Education, Inc.

Published: January 2, 2013 171

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Table 1. New First- and Second-Year Lecture Curriculum Course Name CHEM IL: Atomic and Molecular Structure

CHEM IIL: Structure and Function of Organic Molecules I

CHEM IIIL: Transformations of Organic Molecules

Topic Coverage Atomic Structure: structure of atoms; subatomic particles; nuclear chemistry; quantum theory; periodic trends Molecular Structure: bonding theories; Lewis structures; structure−reactivity relationships; forces of stabilization Analysis of Structure: symmetry analysis via VSEPR; atomic methods; molecular methods Advanced Gaseous Chemistry Liquids, Solids, and Solution Chemistry: properties of states of matter Hydrocarbons: nomenclature; conformational analysis; stereoisomerism; elementary thermodynamic calculations; elementary reactions Advanced MO Theory: LCAO methods; perturbation theory; HOMO−LUMO applied to reactions Reactivity of Molecules: gaseous state reactions; introductory thermodynamics and kinetics; kinetics applied to mechanism determination; classes of mechanisms; selectivity; reactive intermediates Acidity and Basicity: definitions and structural characteristics; linking Lewis theory to electrophile−nucleophile designation; HSAB theory; equilibrium position of acid/base reactions Nucleophilic Substitution and Elimination: factors influencing mechanistic pathway Electrophilic Addition Oxidation and Reduction: organic and inorganic contexts Aromaticity: Huckel’s rule; aromaticity determinants; EAS and NAS; analysis of reactions Liquids, Solids, and Solution Chemistry: solvolysis, solid state organic chemistry Alcohol and Ether Chemistry Carbonyl Chemistry and Chemical Equilibrium: aldehydes and ketones; carboxylic acids and derivatives; reactions at the α carbon; intermediate equilibrium concepts Organometallic Chemistry: Coordination compounds; classical syntheses and preparations; newer applications toward organic synthesis Pericyclic Reactions Introductory Biochemistry: Classes of biomolecules

substantially in instrumentation to support undergraduate education at all levels, but most especially in the first- and second-year laboratories. The new CPT guidelines21 provided greater latitude for the re-evaluation of course design and strategy. Together, these influences led to the development of a modified blended curriculum during the first two years of instruction, where fundamental concepts of chemistry are emphasized using both inorganic and organic contexts. Four new required courses, three lecture courses with co-requisite labs and one stand-alone laboratory course, were created to meet these criteria; Table 1 describes the three lecture courses in greater detail. The focus of this article is on the four new laboratory courses. To enroll in this course sequence, students must have completed one year of high school chemistry with either an A or B grade. These courses are intended for incoming students who have declared either a major in chemistry or biochemistry; students from other majors who meet admissions standards of the Honors College also are eligible to enroll in these courses. The chemistry and biochemistry department is committed to creating strong ties to the majors as early as possible to make them feel welcomed into the department from the earliest days of their undergraduate education; the course sequence described here is a foundational aspect of that commitment. The department also offers the more traditional first-year general chemistry sequence and the second-year organic chemistry sequence in support of other science and engineering programs on campus. Students who begin in the course sequence for chemistry or biochemistry majors are strongly encouraged to complete the courses, chiefly because of the sequential nature of the courses and other pre- and co-requisite coursework. However, mechanisms are in place for students who wish to change majors while in these courses. For instance, a student who enters her or his first year as a biochemistry major and who later decides to change majors may either (a) complete the course sequence or (b) move into the traditional

sequence of courses, depending upon the requirements of the newly declared major. Our department has worked extensively with other departments on campus to ensure that students who change into and out of our majors’ courses are not at a disadvantage for timely completion of their chosen degree path. We further have worked with administration to allow the firstyear courses (CHEM IL and CHEM IIL) to meet system graduation requirements. The first three lecture courses (CHEM IL through CHEM IIIL) each have a laboratory co-requisite that is graded independently. The lecture courses carry three credit hours and the associated laboratory courses carry one credit hour. As such, laboratory meetings occur once per week for three hours. Henceforth in this description, we refer to each lecture course, and the associated co-requisite laboratory courses, as CHEM I through CHEM III. CHEM IV refers to the stand-alone laboratory course designed as the capstone for this sequence. Students purchase both general chemistry and organic chemistry texts for all three courses, with no formal text required for the laboratory co-requisite or capstone courses. Annotated syllabi for the lecture and laboratory components of CHEM I and CHEM III are found in the Supporting Information. Reconceptualizing the lecture courses naturally led to reconceptualizing the corresponding laboratory program. The overarching goal of the laboratory redesign for the first four semesters was to closely mirror the process of entering a working research laboratory as a functioning member of the research team. To achieve this goal, three guiding principles were considered: • Research is a process that involves a community of practitioners with varying roles and responsibilities to the community22 • Learning laboratory techniques should intellectually progress from mastery of skills toward open inquiry 172

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Table 2. Laboratory Interactions in CHEM I and CHEM III Week 1

CHEM I Activities Syllabus and Expectations Solution preparation; Lab techniques UV−vis Theory: LabQuest operation; Beer−Lambert law; standard curve generation

2

Interactions

CHEM III Activities

Introductions and team-building exercise

Syllabus and Expectations

How can UV−vis standard methods be used to determine the best source of lycopene?

Extraction of lycopene from various tomatobased foodstuffs Extraction of lycopene from nutritional supplements Oxidation of alcohols using NaOCl solution Oxidation of alcohols using NaOCl solutions of various concentrations Solventless aldol The Fischer esterification

3

UV−vis: quantitative assessment of lycopene in tomato-based foodstuffs and supplements



4

Standardization of NaOCl by titration

5

FTIR: Theory and instrument operation; obtain spectra for alcohols and oxidation products

Using FTIR, how do we determine the impact of bleach concentration on the oxidation reaction of alcohols? 

6 7

Atomic Absorption Theory : analysis of Ca in cereal HPLC/GC theory and hands on training: quantitation via HPLC and qualitative description via GC of sample esters HPLC/GC theory and hands on training

No Group Problem to Solve Using a standard curve, how do you optimize reaction conditions for an organic reaction? 

HPLC ester analysis using the retention times from GC and standard curves from HPLC 1 H and 13C NMR: example spectral interpretation



8 9 10 11 12 13

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How do you determine if a chemical transformation is completed? Interpretation of 1H NMR spectra of methyl red reagents and  products Mass Spectrometry: theory and example spectral analysis How are small differences in structure determined when a library of compounds is created from one starting material? Interpretation of MS data on a library of compounds 

• Research instrumentation provides greater insight into future learning activities for students who intend to pursue careers in the chemical or biochemical sciences

A mixed Fischer esterification? Analysis of Fischer esterification products Synthesis and purification of methyl red Synthesis of penicillanic acid derivatives Purification of penicillanic acid derivatives 

• Gaining the confidence of more senior members of the community by learning the mores of the community and making contributions to its continuity • Increasing in community status by continually adopting roles that have greater responsibility to the community’s output and continuity CHEM I and CHEM III students co-enroll into one laboratory classroom session, working together to answer an overarching question. In this model, CHEM I students serve as novice chemists, entering the community of practice at its fringe, while CHEM III students serve as more experienced chemists. These CHEM III students serve as mentors to novice CHEM I students, providing experience and guidance in several areas: standard laboratory techniques, the use of instrumentation in appropriate instances, and other ideas related to progress in a laboratory setting. In turn the CHEM I students, by performing peripheral duties, learn from the experiences of their older colleagues to develop the laboratory skills and knowledge required to increase rank and responsibility within the community, knowing that they will be the experienced members of the community in the following year. This structure implies that each group has separate responsibilities that relate to the completion of experiments or projects. The role of graduate teaching assistants and instructors of the laboratory courses is best explained using Liebig’s hierarchical model. The model is based on a pyramidal shape, where at its base are undergraduate research assistants just beginning their research experiences, and at its apex is the research advisor, from whom research ideas and projects are derived. In between these strata are more advanced undergraduate students, beginning graduate students, senior graduate students, and postdoctoral researchers. Liebig’s model is congruent with the theory of legitimate peripheral participation, in that to ascend the pyramid of the research lab hierarchy a student must prove her or his abilities to more senior members, who have already

STRUCTURE AND RATIONALE OF THE PROGRAM The programmatic structure of the pedagogical model is described below, in the context of each guiding principle. Table 2 illustrates the interactions and expectations of CHEM I and CHEM III laboratory students in a typical fall semester. The more open-ended laboratory explorations that occur in CHEM IV make it more difficult to predict interactions these students may have with CHEM II students, even though co-enrollment and collaboration still occur. Readers may find it helpful to refer to Table 2 when reading the contents of this section for examples of collaboration, community building exercises, and standard technique skills acquisition through the courses described. Developing the Community of Practice

One of the overarching goals of the pedagogical model presented here is to develop a community of practitioners who work collaboratively to address a common question. The model is based in part on Lave and Wenger’s22 theory of legitimate peripheral participation and in part on Liebig’s model of research laboratory hierarchy.23 The theory of legitimate peripheral participation purports that those who join a community of practice increase their participation and status in the community through involvement in at least one of the following experiences: • Entering the community at its periphery, where lowresponsibility tasks are given that remain vital to the continuity of the community and its purpose • Proving themselves by doing work that alone is considered unimportant, but is vital to the continuity of the community and its practice 173

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and create actual solutions for the activity. The activity is designed to demonstrate how the guiding question integrates the work of the two cohorts that, when combined, will answer the guiding question. The expectation that this general type of collaboration will continue through the semester is reiterated such that students understand how the collaborative community functions. Students naturally are curious about the evaluation procedures of the course. In the pedagogical model, assessment procedures reflect both the individual and collaborative aspects of each laboratory activity. The laboratory activity is defined in this context as a multiweek exercise. Student groups complete three specific group assessment tasks for each laboratory activity while the members of specific cohorts complete two assessment tasks. The three overall group assessments include (1) formulating task lists (during the first laboratory period), (2) creating an implementation plan (completed outside of lab after the first week), and (3) answering the guiding question in a final summary statement. The specific cohort assessments involve completing a memo describing their actions and plans in each laboratory session. Most of the activities utilized in the laboratory courses are two weeks in length, resulting in two memos; generally a memo is completed for each week of the duration of the laboratory activity. At various points during the laboratory activity, student groups come together to discuss progress toward answering the guiding question. The assessment strategy makes use of rubrics to assign points for each of the five assessment tasks. The methods and implementation plan for this lab curriculum redesign, based on specific laboratory activities and guiding questions, will be described in detail in the forthcoming implementation paper.

accomplished ascension by virtue of their previous work. In this model, following the Liebig approach, the instructors of the laboratory courses serve as the research advisor, and graduate teaching assistants are equivalent to postdoctoral researchers. The instructors’ responsibilities are to devise activities for students in the lab courses, and the graduate teaching assistants are present to provide advice or expertise when students encounter problems completing their assigned activities. Similarly, CHEM III students are akin to more senior graduate students, while CHEM I students are considered beginning graduate students. Several programmatic aspects of the model support community development, including co-enrolling students from different courses (CHEM I and CHEM III; CHEM II and CHEM IV) simultaneously into the same laboratory space, creating choreographed interactions between the different cohorts, devising separate yet related exercises for each cohort, and unifying the experience with a common question that, alone, neither group of students could adequately answer. These elements require substantial prior planning, involving first the teaching team (teaching assistants and instructors), and then the students who enroll in the courses. Open communication is vital to the success of the model, as expectations and responsibilities are explained. Before the beginning of each semester, the instructional team meets to discuss the pedagogical model and its intended outcomes. These meetings are intended as small, in-service training for teaching assistants; teaching assistants are provided with the first laboratory activity, complete with instructor notes and hints. Teaching assistants discuss strategies with instructors related to helping students to become independent, creative, and productive members of the community of practice. They also come to learn their own role in the community as that of resident expert and facilitator of question asking and answering ability. This model provides opportunities for acquisition of pedagogical knowledge that most teaching assistants do not experience via teaching traditional, expository laboratory exercises; consequently, not only are undergraduates trained in the mores of a functional research group, so too are graduate students but from an instructional viewpoint. The teaching assistants assigned to these laboratory courses are instructed on how to answer student questions with questions, how to allow students to pursue incorrect strategies, and how to observe interactions that are productive to community development. If the goal is to mimic the community of practice in a working research laboratory, the teaching assistants play a vital role in helping students acquire the skills and knowledge to climb the ranks of the community as a whole. The instructional team also meets weekly to discuss upcoming collaborative laboratory activities, and methods to facilitate the development of community among the undergraduate students. When the semester begins, the first laboratory period includes a general discussion of the goals of the model, and the roles and responsibilities of each member of the community: students from different cohorts, teaching assistants, instructors, and faculty members (when applicable). Student groups, formed by combining members from CHEM I and CHEM III, are provided with an example of how community building occurs through the implementation of an actual laboratory exercise to create specific aqueous solutions; open discussion is encouraged. The choreography for this community building exercise involves requiring CHEM III students to assist CHEM I students to complete calculations

Moving from Verification to Inquiry

The pedagogical model includes the implicit assumption that students enter their academic training with inadequate understanding of instrumentation and the standard repertoire of laboratory techniques used by practicing chemists. This assumption guided the curriculum redesign strategy; students must initially be provided with basic training in laboratory technique and the use of instrumentation, and as they progress through the curriculum, laboratory activities must not only reinforce these skills but introduce new skills such as control of experimental variables, experimental design, and combinatorial analytic techniques. Thus, the pedagogical model was created to first teach students the repertoire of laboratory techniques and progress from there to the design and implementation of experimental procedures related to departmental research initiatives. CHEM I is designed to introduce students to the instrumentation described above, as well as to acquire laboratory skills necessary for progression to mastery. These laboratory skills include volumetric techniques, titrations, standard solution preparation, and understanding the utility of creating a standard curve. These activities correspond to level 0 in the Bruck, Bretz, and Towns17 characterization of inquiry activities in a laboratory setting. CHEM II emphasizes continued use of the laboratory instrumentation, in addition to teaching students the typical organic chemistry laboratory techniques: distillation, recrystallization, chromatographic techniques, and the like. CHEM II provides a different context of learning for students; experiments focus on elementary investigations of organic reactions (e.g., substitution and elimination), typical workup strategies for isolating organic 174

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instructors, and faculty mentors (Bruck, Bretz, and Towns level 2 and 3, guided and authentic inquiry, respectively). The continued use of research-grade instrumentation is a central theme of the course. Student teams are responsible for completing a literature review related to the chosen topic, designing and implementing experiments to answer research questions, and choosing the appropriate analytic techniques to verify the outcomes of their experimental procedures. Support for these activities is built into the course, including teaching assistants, instructors, graduate students, and faculty members. CHEM IV students are expected to present periodic progress updates to their faculty mentors, as well as their teaching assistant and peers. They also write weekly memos outlining the activities they plan to complete in the week, and the experience ends with the creation of a poster, which is presented at the university’s annual undergraduate scholarship and creativity day. These activities aid students’ in building written and oral communication skills.

reaction products, and the use of instrumentation to analyze the outcomes of these reactions (Bruck, Bretz, and Towns level 0, confirmation). Additionally, CHEM II students begin to learn the process of variable control in experimental procedures. For example, two weeks of laboratory instruction are allowed for both substitution and elimination reactions. Rather than providing expository experimental procedures to learn about these reactions, students are provided with a list of available chemicals, and instructed to create a series of three experiments where two variables are held constant while one variable is changed (Bruck, Bretz, and Towns levels 1/2 and 1, structured and guided inquiry, respectively). The first week of the exercise is devoted to experimental design, whereas the second week is the execution and analysis of their designs. Students must present their designs to the teaching assistant at the end of the first week, and the teaching assistant is encouraged to ask probing questions of the student groups to ensure that a proper understanding of variable control is achieved. Teaching assistants are also encouraged to allow students to improperly design experiments and not “over-correct” student strategies. In this way, students learn from their mistakes, much as practicing scientists do in research laboratories. CHEM III emphasizes more advanced synthetic processes, including multistep syntheses. Here, students refine their synthesis, product isolation, and product verification skills. In keeping with a movement toward more inquiry driven learning opportunities, students now are provided opportunity to design and execute their own syntheses (Bruck, Bretz, and Towns level 2, guided inquiry). For example, when investigating electrophilic aromatic substitution (EAS) reactions, adding substituents to an aromatic starting material requires careful planning to achieve the synthetic target. In previous iterations of the course, students designed a synthesis of benzocaine. This laboratory exercise is standard in many organic chemistry courses, but in this model, students are not provided with the target molecule until they arrive in lab. The first week they devise a strategy using a given starting material and other reagents as necessary, without the use of textbooks or the Internet. Their knowledge of EAS and the teaching assistant are the only sources of information for planning the synthesis. Attention to detail is required as well: what is the appropriate solvent? How long should the reaction be allowed to reflux? Will the substituent added to the starting material be placed where it should be to reach the target? Again, teaching assistants allow the students to make errors in their strategies, mimicking many an attempt at synthesis in a research lab setting. The three semesters’ training in instrumentation, inorganic and organic laboratory techniques, and experimental design are brought to bear in CHEM IV, which emphasizes an openinquiry approach and was designed to be a springboard to authentic undergraduate research participation. In this course, students work with research-active faculty, who present their research initiatives to the students. Students then assemble into teams for a semester-long investigation of the research problems presented by the faculty members. In previous offerings of the course, students have devised analytic strategies to determine caffeine metabolites in a biological matrix (rat urine), green syntheses of organic compounds, reaction optimization studies, and analytic methods to determine chemical warfare reagent exposure. In each of these projects, procedures and outcomes are unknown both to students,

Using Advanced Instrumentation Early in Academic Training

The instructional model is built around a theme of hands-on use of research grade instrumentation as early as possible in the academic training of future chemical scientists. From the first semester of academic training, students are introduced to and conduct laboratory experiments using advanced instrumentation. The instrumentation used in support of thisinstructional model was chosen based on two factors: the perceived need (by faculty) of these instruments in the teaching laboratory and the rate of use of these instruments in departmental research activities. As the capstone of the redesigned laboratory curriculum is the infusion of faculty-driven student projects in CHEM IV, it is necessary to familiarize students with specific types of instrumentation and the appropriate circumstances under which to use it. Therefore, gas chromatography (GC), high-performance liquid chromatography (HPLC), FT-IR, atomic absorption spectroscopy (AA), mass spectrometry (MS), and nuclear magnetic resonance spectroscopy (NMR) were chosen by faculty as the most important instruments that a beginning undergraduate chemistry or biochemistry major should understand. The emphasis of CHEM I lab is to introduce students to the theory and application of the instrumentation listed in the previous paragraph. Typically, two weeks are devoted to each instrument used with the exception of AA spectroscopy (given one week). The first week, CHEM I students learn the theory of the instrument, including the qualitative and quantitative uses of the data provided by the instrument in question. Simultaneously, CHEM III students are typically involved in the synthesis of organic molecules, which reinforces the use of organic laboratory techniques for them. The second week is devoted to working with the instrument to acquire data (CHEM I) and to analyze the outcomes of reactions run previously (CHEM III). CHEM I students, having learned the theory of the instrument in the first week, now collaborate with CHEM III students to gather data with the instrument using samples provided by CHEM III students. This pedagogical arrangement builds a collaborative work environment: CHEM III students must verify that their synthesis worked using the proof of spectral data, which is provided to them in part by their CHEM I collaborators. Literature precedent indicates that continued use of instrumentation in laboratory settings increases student 175

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program is to simply create a laboratory-based course targeted at second-semester second-year chemistry majors, akin to CHEM IV. Research-active faculty can participate in the development of the course and the projects students will investigate and the extent of inquiry instruction can be guided in part by the instrumentation maintained by the department in question. Alternatively, such a course might focus on servicelearning aspects of the chemical sciences, to incorporate a sense of community stewardship in early career college students. We also advocate expanding the model to include other subdisciplines of chemistry that might lead to interesting and fruitful collaboration between courses. For instance, a course in instrumental analysis might pair with an environmental chemistry course to create a number of projects where students work together to answer common questions using various techniques. A simpler adaptation may involve aligning two experiments from two different laboratory courses so that students from one are responsible for analyzing results from the other. In this way, a department may experiment with different adaptations to determine which, if any, best suits their instructional needs and goals.

confidence and empowerment to use these instruments in future applications and different settings.18,19 We assert that, because these instruments are extensively used in both advanced laboratory courses and departmental research initiatives, the introduction of students to this equipment and its use at early stages of a student’s cognitive development and academic training is particularly appropriate, and likely will facilitate transfer of skills and knowledge regarding these instruments to similar settings in future laboratory activities.

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PRELIMINARY OUTCOMES

Currently, formal evaluation procedures have been implemented to determine the impacts of thismodel of laboratory instruction; some variables under examination include criticalthinking ability, retention of concepts and skills, time of entry into undergraduate research participation, and perpetuation in both the research laboratory and completing the B.S. degree. The latter two metrics will be measured and compared with departmental records from previous academic years to determine if this approach propels students into undergraduate research earlier and keeps them active longer. Further, the CAT, or Critical Thinking Assessment Test,24 will be used to determine whether the model improves students’ criticalthinking abilities by comparing CAT results with students who experienced traditional instruction in the first- and second-year laboratory courses. Anecdotally, some positive changes in student attitudes toward research participation were noted compared with previous years in the traditional sequence. First, of the 28 students in the first cohort to complete the sequence, six students participated in research during the summer following CHEM IV. Three of these six participated in projects that were a continuation of the project they investigated in CHEM IV. Four of the 28 were placed into competitive undergraduate research fellowships in national laboratories or industrial settings. Additionally, three other students had begun the process of finding research opportunities on campus in the fall 2011 semester. In total, nearly half of the first cohort either has participated or is participating in some form of research activity at the completion of their second year. For the conventional laboratory instructional methods in previous years, most undergraduate research assistants (83% according to departmental records) did not begin authentic research participation until the second semester of their third year. We believe that our laboratory model is partially responsible for earlier entry to authentic research activities. Informal conversations with students who have completed the laboratory sequence indicate that they feel more advanced in their thinking and skills attainment than their peers who completed the traditional laboratory sequence. Further, most have stated that the new curriculum was far more interesting and engaging than that reported by their peers in the traditional courses.

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CONCLUSION This model represents an innovative instructional approach to chemistry laboratory courses during the first two years of academic training. The model allows for greater interaction between cohorts of students, both in and out of the laboratory setting, which in turn leads to a strengthened sense of belonging in a community of practice. The practice perpetuates to include the departmental research community, in whose laboratories the students will eventually participate as research assistants. This model also introduces students to faculty research interests at an earlier stage of academic development, with the purpose of smoothing the transition into a research laboratory setting earlier in their academic careers. Constructing the community of practitioners around open-inquiry, faculty-driven research projects provides students with the intellectual development necessary to fully realize their potential as future chemists and hopefully will ensure long, productive careers.

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ASSOCIATED CONTENT

S Supporting Information *

Annotated syllabi for the lecture and laboratory components of CHEM I and CHEM III. 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

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The authors declare no competing financial interest.

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APPLICABILITY The model described has been successful, in large part because chemistry and biochemistry majors are placed into introductory courses designed for them from the beginning of their academic careers. Although other institutions may not separate chemistry and biochemistry majors from other science majors in their introductory coursework, we believe that, with creativity and initiative, modifications to our model can successfully translate to institutions of varying sizes. A possible adaptation to this

ACKNOWLEDGMENTS We gratefully acknowledge the National Science Foundation, Division of Undergraduate Education, for their financial support to purchase instruments for the teaching laboratory (TUES Grant #1044419). The authors also acknowledge the support and patience of the Chemistry and Biochemistry Department faculty at South Dakota State University. Without their support, the community we describe could not exist. We 176

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also thank the first and second cohorts of students who have experienced the new curriculum for their willingness to serve as test cases in this pedagogical experiment. Finally, gratitude also is extended to the graduate teaching assistants who helped in the design and implementation of the model.

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(21) American Chemical Society. Undergraduate Professional Education in Chemistry: ACS Guidelines and Evaluation Procedures for Bachelor’s Degree Programs; ACS Publications: Washington, DC, 2008. (22) Lave, J.; Wenger, E. Situated Learning: Legitimate Peripheral Participation; Cambridge University Press: Cambridge, U.K., 1991. (23) Fruton, J. The Liebig research group: A reappraisal. Proc. Am. Phil. Soc. 1988, 132, 1−66. (24) Stein, B.; Haynes, A.; Redding, M.; Ennis, T.; Cecil, M. Assessing Critical Thinking in STEM and Beyond. In Innovations in eLearning, Instruction Technology, Assessment, and Engineering Education; Iskander, M., Ed.; Springer: New York, 2007; p 79.

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