role-playing in the undergraduate laboratory - ACS Publications

which Walters calls a "role-playing" laboratory, had its genesis at the Uni- versity of Wisconsin—Madison in 1968 and evolved as he recognized the n...
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ROLE-PLAYING IN THE UNDERGRADUATE LABORATORY

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sk a group of analytical chemists to describe their experiences in undergraduate analytical chemistry classes, and most would probably recount a series of sometimes dry theoretical lectures, followed by a series of laboratory sessions that seldom reflected their professors' excitement about analytical problem solving. Detailed directions guided students who competed with one another as they performed cookbook experiments. Grades depended primarily on developing basic laboratory skills and on how closely the results obtained corresponded to some standard value. The interpersonal skills that would be essential for success in the students' professional lives were learned later, either in graduate school or through on-the-job training. John Walters, professor of chemistry of St. Olaf College in Northfield, MN, thinks that there is a better way to teach future generations of analytical chemists. He has devised a curriculum that adds realism to the analytical laboratory and allows students to learn new chemistry while simultaneously

learning management and leadership responsibilities. This cooperative learning approach, which Walters calls a "role-playing" laboratory, had its genesis at the University of Wisconsin—Madison in 1968 and evolved as he recognized the need to enhance the extent to which students interacted with one another.

FOCUS During his 17 years at Madison in large analytical labs, he observed that genuine understanding was promoted by individual interaction—one person teaching another what he or she knew. At St. Olaf, where the classes were much smaller, he found that trying to achieve greater interaction by pairing students generally resulted in a dominant-dependent duo. According to Walters, "A different vehicle was necessary to promote division of responsibility, not simply encourage the division of labor."

What is role-playing? Role-playing is a technique in which the participants adopt and act out deliberately exaggerated cultural stereotypes to explore what it would be like to have any or all of the stereotype's properties. When undertaken in the chemistry laboratory in a group setting, the technique allows students to act out roles such as a Ph.D.-level manager of an industrial research group and to develop individual technical expertise. At the same time, students receive a hands-on introduction to the importance and development of communication and collaboration skills—tools that they will need to become successful professionals. They can explore new roles in an atmosphere that encourages cooperative problem solving and allows mistakes to be made without personal risk. Two fundamental principles guide the application of role-playing in Walters' classes. First, all laboratory work involves interdependence among skilled individuals working together.

ANALYTICAL CHEMISTRY, VOL. 63, NO. 6, MARCH 15, 1991 · 347 A

FOCUS

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M

Week 11 S Week HWeek 3 21 CIWeek 4 D) S H C M

Hj[SJÎMj[ÇUr3 .SI

M C H C Figure 1. Example of role rotations for a block of four experiments. The roles are M (Manager), C (Chemist), S (Software), and H (Hardware). A, B, C, and D indicate bench positions. (Courtesy John Walters.)

Second, all work is based on division of responsibilities rather than division of labor. Members of groups are encouraged to be interdependent by designing experiments with objectives and problems that are best solved by collaboration. Each person is responsible for part of the solution, but the total solution is apparent only when all the pieces are in place and after discussion among the group members. In this structure, the professor still creates the lab experiments and the course standards. The part of his or her role most visible to the students, however, changes from that of an authority figure to that of "paid consultant." Walters is paid with apples, a fee that he thinks removes the authority aspect of his position without harming its leadership credibility. Student roles Students are divided into groups of four, called companies. Four companies comprise a lab section, and multiple lab sections form a course. The members of each company adopt four roles: Manager, Chemist, Hardware, and Software. These roles are played individually and are rotated (see Figure 1) so that everyone plays each role at least once and preferably twice during a semester. During the course, students are referred to by the name of the role they are playing rather than by their given names. This important distinction has the advantage of facilitating honest and open communication. Students can discuss difficulties encountered with the role rather than with the person playing it. Role names suggest how the responsibilities should be divided among com-

pany members as they perform a given experiment. Each role has some general responsibilities and some that are specific for a given experiment. Manager is the only person responsible for the organization, implementation, outcome, and reporting of experimental results. He or she prepares all reports and sends the information by electronic mail to the person(s) to whom the company is responsible ("upper management"). This role is accountable for the quality of the communication among other role-players. Finally, Manager receives the grade for the entire effort, and all other company members receive that same grade. Chemist is responsible for the reagents and analytical standards needed to implement Manager's plan for the experiment. This person must prepare and deliver these materials in the correct chemical form at the appropriate time and place. Hardware is accountable for operation and any assembly of the instrumentation needed to carry out Manager's plan. Software is responsible for creating, linking, and operating any software that the other three roles require to fulfill Manager's plan for the experiment. This person also sets up the telecommunication program that Manager uses to communicate experimental results. As might be expected, students who undertake the role of Manager often have little or no experience in this area, and some outside reading about management theory is well advised. Walters suggests four popular books that touch on small-group dynamics, giving and receiving feedback, and successful as well as unsuccessful management styles for problem solving in small groups. Physical laboratory layout The analytical laboratory at St. Olaf has four traditional benches in the center of the room and two large end benches with four hoods. Each center bench has a wet and a dry end; the physical location receives a company name such as Wendy, Laura, Bruce, or Deano. The reality of the situation is thus enhanced by having a small, identified community t h a t is properly equipped for the task at hand: problem solving. Each lab bench is connected to a Hewlett-Packard 80386 Xenix-based course microcomputer by a 19 200baud line. Instrumentation on the bench varies according to course level. For the junior course, each company has digital analytical and top-loading balances, a dual-beam spectrophotom-

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eter and strip-chart recorder, a liquid chromatograph, a digital pH meter, a colorimeter with digital readout, and a magnetic stirrer. In the future, Walters plans to add an electrochemical analyzer to each company's instruments and a robot that would operate in the center portion of each bench. In the senior course, students set up computer interfacing equipment at the beginning of the semester. As the course progresses, this equipment serves the instrumentation on both the wet and dry ends of the bench. Both classes make use of larger instruments (i.e., atomic absorption spectrometer, gas chromatograph/mass spectrometer, and an FT-IR spectrometer) outside the laboratory, but their "home base" remains the physical company, or laboratory bench. To extend communication between individual companies, each can use the company computer and executive terminal present on each bench. Course microcomputer The course microcomputer contains the results achieved by past analytical classes, and students are encouraged to consult these archives. The computer enhances timely reporting, advance preparation, and in-lab communication through electronic mail. It is designed to act as the center for software and data that Manager and Software use to design and report experiments, and is set up with 16 serial ports and one parallel port. Eight serial ports connect at 19 200 baud to each lab company; one connects to provide 2400baud time-sharing among the college's VAX machines, 12 dial-in lines, and public microcomputers and terminals; two serve the professor's office; four connect to a robotics research lab; and the remaining port is connected to a 9600-baud modem that allows facile communication with outside labs, offices, and networks. Printers are serviced from the parallel port. Four software programs that enable Manager and Software to prepare the needed quality reports and spreadsheets are installed on the microcomputer. They include a word processing (Lyrix), a spreadsheet (SCO Professional), and a database program (Foxbase+) as well as two programmable smart terminal programs (DEJAVU and TERM). Other local software to transfer programs and edit text is also installed. Courses Each of the four student roles is introduced and adopted in a series of three courses, as indicated in Figure 2. The introductory course, taken primarily

Junior course

Sophomore course

Senior course

Chemical methods of analysis

Uses of computers in the health-related professions

Instrumental methods of analysis

(Quality control)

(Methods development)

Manager (Organization of the experiment)

Word processing

Manager (Design of the experiment)

Chemist (Manipulation of the solutions)

Spreadsheet use

Hardware (Assembly of the instrument)

Software (Collection of the data)

Database design

Software (Processing of the data)

Hardware (Operation of the instrument)

Data telemetry

Chemist (Preparation of the solutions)

Figure 2. Courses comprising the role-playing analytical curriculum and the responsibilities associated with the roles played. (Courtesy John Walters.)

by sophomores and juniors, is a onemonth intensive class held during the college's winter interim session to help develop the level of computer literacy required in the higher level courses. It also helps in developing the other roleplaying laboratories by serving as a software development test site. The junior-level course, Chemical Methods of Analysis, is the largest of the three; enrollments have ranged from 27 to 65 in the past seven years. Its atmosphere is one of production quality control, and the experiments undertaken here are received in essentially complete form from the seniorlevel Instrumental Methods of Analysis course. In fact, the product of the senior course companies is methods development of experiments for the junior course (the customers). This setup encourages the service emphasis and allows students to explore a mature blend of methodology and instrumentation. They understand and can identify with the notion that their experiment will eventually be adopted by students who will be at the same skill level as the developers were one year before. Roles receive different emphasis in the junior- and senior-level courses, and this is conveyed in both the written material presented and the verbal instructions provided in lectures and other meetings. For example, in the junior course, Manager's responsibility is primarily one of organization, whereas in the senior course, that emphasis shifts to design. Figure 2 indicates these differences in all four roles.

Experiment objectives and design The role-playing experiments in Walters' classes were developed from his own practical professional experience and from textbooks. The latter experiments are used to train students in proper laboratory techniques and to let them explore the roles to be assumed when they encounter problem-solving objectives. The problem-solving objectives, together with the structure and equipment available, are central to the sources of this curriculum, says Walters. Objectives must be manageable within the context of the course, but they must also be creative and interesting to the students. In large part, they reflect the four functions of a professional analytical chemist: chemical analysis, methods development, instrument development, and basic research. The experiments developed to date largely reflect the first two functions mentioned above. For the junior course, there are quality-control experiments; for the senior course, there are methods development ones. The experiments are further divided into basic training (technique oriented) and problem solving (management oriented). Tables I and II (pp. 350 A and 352 A) indicate junior- and senior-level experiments and objectives. Basic training or role-defining experiments establish the importance of dividing responsibility. In the junior course, these experiments cement the

concept that the accuracy of a given method depends on the various degrees of error propagation, which can be directly attributed to different levels of mastery of laboratory technique. Statistical data treatment is emphasized, and the concept of accountability for management is stressed. At the senior level, basic training experiments cover computer interfacing and are undertaken individually because students generally have little, if any, knowledge of how to use a computer for instrument control or real-time collection of data, and these skills are essential for the experiments that follow. At the next level of experiments in the senior course (role practicing or interstitial), the interdependence of the roles is stressed and primary emphasis is placed on methods development. Specific experiments involve building a DME polarograph, using A/D and D/A converters, automating the dual-beam spectrophotometer as a remotely operated instrument, and developing a remote analytical method. The polarography experiments place sophisticated demands on Hardware, require that Manager make some compromises because of the equipment involved, and quickly bring home the fact that chemistry and hardware can be closely combined under software control so that one can study fundamental physical processes. A new experiment on robotics using a Zymark lab robot is also being developed. In the remote-control experiments, Hardware and Software can communicate only through an intercom. Manager aids this process and arbitrates such questions as how much data should be taken, whether it should be stored, and what should be done after it is stored. Although the mechanics of gathering data are routine, students learn by assuming responsibilities while the pro-, cess is under way. The final set of experiments involves true role-playing in areas that are research-like but can be managed in the undergraduate laboratory. Eight such experiments have been developed, four each for the junior- and senior-level courses (see Tables I and II). In each experiment, the objective is stated as a target goal, but Manager is free to achieve it in whatever way seems best. All have explicit ethical overtones in addition to the normal technical compromises present in practical research and analysis. Consider, for example, the junior course's "Edible Easter Egg Grass Dilemma." The problem requires students to analyze a competitor's product. Is the product composed of the same combination of food dyes as the

ANALYTICAL CHEMISTRY, VOL. 63, NO. 6, MARCH 15, 1991 · 349 A

FOCUS company's product? Manager must de­ cide how to design and perform the spectrophotometry. Chemist is respon­ sible for preparing the appropriate concentrations of standard solutions, and Hardware must handle the dynam­ ic operation of the spectrophotometer. Software and Manager must consult about how to analyze the data to get the necessary information so that Manager can decide whether to challenge the competitor's advertising claims. Wal­ ters points out that this problem has produced interesting small-group dy­ namics and is solidly based in instru­ mental analysis. Another example with real-life ap­ plicability is the senior course's "In­ strument Payment Release Problem." The company has purchased a liquid chromatograph, and Manager must de­ cide whether to release funds allocated for its purchase. The decision is based on input from the other roles as to whether the instrument is performing according to specification. The choice of mobile phase composition, as well as test compounds, is left open, and Hard­ ware must decide how data can be ac­

quired. Chemist's job is affected by the decision Hardware makes, and Manag­ er must not only make the final deci­ sion but also determine whether in­ strument performance has been ade­ quately investigated by the test mixture selected. Grading The role-playing laboratory awards grades based on the principle that good management produces good results; thus, the results themselves are not graded—management is. How can this be done objectively in a given experi­ ment? Upper management must indi­ cate what it values and sets as objec­ tives. According to Walters, good man­ agement happens if the company Manager understands the value system and meets the experimental objectives. Before the experiment begins, each Manager is told in writing which values are important to upper management and is scheduled for a management in­ terview with Walters, during which he or she will receive a grade for the com­ pany's effort.

Information used to set the grade comes from three sources. The first is the actual laboratory data and inter­ preted results, which are sent to Wal­ ters by electronic mail. This informa­ tion can be considered the electronic equivalent of the laboratory notebook. The second source is the information Walters gleans from informal queries made of company employees while they are working on a problem. The goal here is to ascertain whether they know what their fellow role-players are doing and how their responsibilities are related to those of the others. Walters mails his observations electronically to Manager shortly after the end of the laboratory session. The third source of information is a brief narrative summary of the experi­ ment that Manager mails to Walters before the management interview is held. At the time he or she prepares the summary, Manager has access to the information contained in the electronic laboratory notebook and to upper management's observations. The interview is an informal discus­ sion, started by a series of eight ques-

Table 1. Role objectives and responsibilities for the senior instrumental analysis course3 Laboratory safety procedures

Manager

Introduction to laboratory computing Basic training (role-defining) experiments Digital data acquisition and display Learn bidirectional I/O Learn binary I/O registers Learn byte parallel input Display pH meter readings Analog data acquisition and display Learn memory-mapped I/O Learn A/D converter control Learn A/D binary/BCD decoding Display skewed GC peak mimic Serial data presentation/telemetry Observe ASCII code on scope Learn serial USART operation Learn terminal emulations Operate instrument remotely D/A converters and operational amps Learn 8-bit D/A converters Build ΟΑ voltage follower Build ΟΑ current follower Assemble polarography amps Interstitial (role-practicing) experiments Build a computer-based polarograph Define CRT display arrays Prepare cation solutions Wire DME/SCE amplifiers Set up A/D and D/A programs Develop a polarographic method Display polarography waves Operate polarographic cell

Manager

a

Hardware

Software

Manager

Chemist

Manager Chemist Hardware Software Manager Chemist

Courtesy John Walters.

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Operate DME/SCE amplifiers Operate A/D/A converters Set up a remote-controlled photometer Define wavelength scans Define weight standards Set up remote connections Set up control programs Develop a remote analytical method Interpret analytical data Prepare weight standards Mimic photometer robot Operate spectrophotometer Problem-solving (role-playing) experiments The plastic spray coating problem Design comparison method Prepare spray samples Operate IBM IR-32 FT-IR Operate IR simulator The pseudo expert system problem Design expert system Dissolve native bronzes Operate Varian AA-750 Operate Lotus spreadsheet The abusive patient drug problem Prepare clinical report Prepare barbiturate standards Operate HP 5870 GC/MS Identify fragmentations The instrument payment release problem Specify acceptance criteria Prepare evaluation standards Operate PE Tri-Det LC Operate Lotus spreadsheet

Hardware Software Manager Chemist Hardware Software Manager Chemist Hardware Software

Manager Chemist Hardware Software Manager Chemist Hardware Software Manager Chemist Hardware Software Manager Chemist Hardware Software

FOCUS Table II. Role objectives and responsibilities for the junior analytical chemistry course3 Laboratory accountability (role-defining) experiments Certification of laboratory operation Certify proper laboratory safety Manager Learn chemical handling and disposal Chemist Learn laboratory information management Software programs Certify lab pH meters and balances Hardware Certification of laboratory glassware Specify calibration procedures Manager Clean and handle glassware Chemist Set up spreadsheet operation and data Software telemetry Set up cable and operate computer/balance Hardware links Basic training (role-practicing) experiments Production quality control lead analysis Manager Design and schedule lab operations Form and digest lead homo/hetero Chemist precipitates Software Set up spreadsheets for statistical testing Set up cable balances to computers for data Hardware collection Statistic evaluation of QC lead data Select and design round-robin statistical Manager tests Collect and correlate homo/hetero lead data Chemist Use spreadsheet for data telemetry Software Operate balances to collect crucible cooling Hardware curves Computer-simulated weak acid titration Design and schedule lab operations Manager Prepare and standardize strong base titrant Chemist Prepare spreadsheet for data acquisition Software Construct pH meter and computer link Hardware Graphical analysis of titration for activity effects Analyze simulated and experimental titraManager tion Prepare and titrate target weak acid Chemist Set up data telemetry and operate simulaSoftware tion Calibrate and operate constructed pH meter Hardware a

Design and training of a mock/real laboratory robot Design spectrophotometric robot method Prepare spectrophotometric solutions Design mock/real robot control language Execute mock robot control language Operation and use of a mock/real laboratory robot Interpret spectrophotometric data Prepare and deliver solutions to hardware Conduct master operation of the mock/real robot Conduct slave operation of the mock/real robot Management dilemma (role-playing) experiments The edible Easter egg grass dilemma Make truth-in-advertising technical/ethical decision Prepare successive dilution color standards Operate spectrophotometer remotely Operate spectrophotometer locally The structural unemployment automation dilemma Make the personnel/productivity decision Prepare weight and volume standards Design error analysis spreadsheet Operate colorimeter and spectrophotometer The broken pill coating machine dilemma Design optimum AA analytical method Dissolve sample and prepare standards Perform least-squares analysis of working curves Operate Varian AA 775 with lab computer The instrument payment release dilemma Determine if HPLC instrument payment is warranted Prepare standard evaluation solutions Operate interfaced computer and spreadsheet Operate interfaced PE Tri-Det HPLC

Manager Chemist Software Hardware

Manager Chemist Software Hardware

Manager Chemist Software Hardware

Manager Chemist Software Hardware

Manager Chemist Software Hardware Manager Chemist Software Hardware

Courtesy John Walters.

tions known to all students at the beginning of the class. They evaluate the communication between all company members during the experiment and the awareness of each role-player about potential effects of their actions on other roles. Manager describes how he or she defined and interpreted the laboratory objectives for company members, how they were adjusted and interpreted as the lab progressed, and whether the objectives were actually met. Techniques used to settle personnel problems are described, and management errors, rewards, and reprimands are discussed. Finally, Manager is asked to describe what type of discussion he or she plans to explain the grade received to the company.

At the end of the interview, Walters identifies problems that range from "fatal flaws" to "minor irritations." Examples of those sufficiently serious to lower grades a full point include failing to note the time and date on critical records that would be necessary to establish intellectual property rights or liability; loss or corruption of electronic data; compensation by Manager for an employee's poor work, which involved redoing it himself or herself later; statistically bad results (measured against the course database and results of the previous semester); and late work. The essential lesson for Manager is to take responsibility for any of the problems identified, regardless of who caused or compounded them.

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Changes and results According to Walters, student acceptance of this laboratory approach has been both enthusiastic and, for the most part, extremely positive. Student laboratories have become more pleasant places to work. He finds that sharing information that allows group decision making, managing, and role-playing is a technique that students value and enjoy. Even when negative reactions are encountered, attitudes are often influenced by the experience of the class. Walters cites the case of a student who resented being asked to manage. She indicated that she didn't want to manage—she wanted only to go to graduate

school. In the management interview after a disastrous lab session, however, she began to view management as a broad concept, and her attitude changed. Walters has also noted other changes in behavior. For example, students are better prepared for laboratory sessions and some even call staff meetings be­ fore the actual session. Those cast as Manager regard their responsibilities seriously and have become distressed when their group members did not take them seriously. He also finds that record keeping im­ proves and that reports are more time­ ly. Some are turned in before the end of the lab, and most before the next lab period begins. Clever solutions to soft­ ware and hardware problems abound, and innovation is not restricted to these roles. For example, Managers have offered food as a tool to motivate other role-players to appear on time. The quality of analytical results has not suffered, and at the same time pro­ ductivity is dramatically enhanced. Good results are obtained with pre-lab planning, often in half or two-thirds of the time that would be required in tra­ ditional classes.

Lectures in both the junior and se­ nior courses have changed as a result of the role-playing laboratory in an effort to reflect the decision making and group interactions introduced in the lab. It is essential, however, that lec­ ture time provide the theoretical basis for the chemistry encountered in the lab. To this end, three factors guide the setup, book selection, and problem as­ signment in the lecture class. First is to communicate the professionally ac­ cepted "conventional wisdom" in mod­ ern analytical chemistry. Second, the material must support and be applica­ ble to the role-playing laboratory. The last factor is the challenging nature of the material, one that reflects the level students will need to be successful in the role-playing laboratory. Industrial support of this approach has been enthusiastic and essential. Funds from companies such as John­ son's Wax Foundation, The Amoco Foundation, the Apple Foundation, The 3M Foundation, and the Dow Chemical Company Foundation have provided equipment for the St. Olaf role-playing lab. Walters believes that the ready availability of a complete in­ strumentation set for each company

greatly enhances the learning process. Students can plan their experiments in advance and perform them in accor­ dance with their own schedules, with­ out the need to sign up for time on a single piece of equipment. To those interested in encouraging students to consider analytical chemis­ try careers, Walters' approach offers great promise. Many of his senior ana­ lytical students go on to graduate school; this year, approximately half of his 11-member class has such plans. Perhaps the most heartening anec­ dote and testimony to the success of role-playing, however, is Walters' rec­ ollection of a particular Friday after­ noon. He found two Managers in the lab at the computer after the lecture final exam, three days after the lab had been checked out, hard at work on a problem. He had to insist that they stop by telling them that he was shut­ ting down the computer—the class really was over. What followed was an afternoon-long discussion of their en­ joyable experiences that ended with one student lamenting about how sad it was "that a person couldn't make their living having this much fun!" Louise Voress

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