A Guided-Inquiry General Chemistry Course - Journal of Chemical

Research: Science and Education

A Guided Inquiry General Chemistry Course John J. Farrell, Richard S. Moog, and James N. Spencer* Department of Chemistry, Franklin and Marshall College, Lancaster, PA 17604

The preceding article (1) describes the philosophical and pedagogical bases of an approach to instruction that differs from the traditional lecture style. Recent developments in cognitive learning theory and classroom research results suggest that students generally experience improved learning when they are actively engaged in the classroom and when they construct their own knowledge following a learning cycle paradigm. In this paper we describe an implementation of these ideas in the instruction of a first-year course in General Chemistry. It is important to emphasize that most of the ideas and approaches described below are not ones for which we can take credit as originators. There is a vast literature on cooperative and collaborative learning, from which we have borrowed extensively (see, for example, refs 2–6 ). The impetus to try a nonlecture approach to chemistry instruction came from a week-long workshop attended by two of us in May 1994.1 We have attended numerous national, regional, and local meetings, read the literature generously, and talked with many other practitioners of innovative teaching approaches. Our goal here is to provide one example of how these ideas may be synthesized into the instruction of general chemistry. Background and Overview of Course Structure Franklin and Marshall College is a private, residential, coeducational college with an undergraduate population of about 1900. For the past several years, about 240 students have enrolled in the first semester of General Chemistry. There is only one type of introductory chemistry offered at Franklin and Marshall, so that students enrolled in this course (and the following second-semester course) include prehealing arts students; potential chemistry, biology, and other science majors; and a few students fulfilling a college distribution requirement. The course is taught in multiple sections of roughly 25 students per section. For the past four academic years, we have instructed our sections of this twosemester general chemistry sequence on the basis of constructivist and learning-cycle principles. This implementation has almost exclusively a student-focused active learning environment, as discussed in the preceding paper. The instructor and student roles are as described there. We are able to achieve this environment owing in part to the particular circumstances at F&M—small class size (~25 students), the location of the laboratory and “lecture” portions of the course in the same room, and the ability to move chairs easily to group students. We who use this approach at F&M all have slightly different ways of implementing it. The description given here is a representative combination of these; it is not meant to be prescriptive, and it is intended only to give a general idea of how the course is conducted.

Consistent with constructivist principles, the major premises of the implementation are that students will learn better when • • • • •

they are actively engaged and thinking in class; they construct knowledge and draw conclusions themselves by analyzing data and discussing ideas; they learn how to work together to understand concepts and solve problems; the instructor serves as a facilitator to assist groups in the learning process; the instructor answers no question that the students can reasonably be expected to answer themselves.

In the basic structure of the course, • • • • •

•

No lectures are given. Students have assigned roles within groups (usually of 4). Groups use Guided Inquiry activities that follow the learning cycle paradigm to develop and learn concepts. A five-minute quiz is given at the beginning of each class on the previous day’s material. There is a textbook for the course, and students are expected to reinforce learning by reading the appropriate sections after introduction of concepts in class. Students are graded individually on hour exams and a final exam.

Student Groups and Roles Almost all of the class time in the course is spent working in groups. There is a substantial literature on the uses of groups and roles in learning environments (e.g., 3–6 ), with varying opinions about different aspects of implementation. The approach we use is based not only on this literature, but also on our experiences with our students. Every day, each member of the group is assigned a new role. When the students each have a specific role, then each is responsible for a particular aspect of the group’s work (in addition to completing the activity), making it less likely that an individual will become disengaged. One reason for assigning roles is to help students develop the various skills that are needed for each of the distinct roles. Often, when students are allowed to choose their own roles within the group, each selects the one with which he or she is most comfortable, and the opportunity to grow in other areas is lost. Below are examples and brief descriptions (given to the students) of some typical roles. Not all roles are necessarily filled on any given day. Manager

Recorder *Email: [email protected].

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Manages the group. Ensures that members are fulfilling their roles, that the assigned tasks are being accomplished on time, and that all members of the group participate in activities and understand the concepts. The instructor responds only to questions from the manager (who must raise his or her hand to be recognized). Records the names and roles of the group members at the beginning of each day. Records the group answers and explanations, along with

Journal of Chemical Education • Vol. 76 No. 4 April 1999 • JChemEd.chem.wisc.edu


Technician

Reflector

Presenter

any other important observations, insights, and so on. The instructor considers the recorder’s answers as the official group response. Performs all technical operations for the group, including the use of a calculator or computer. Unless otherwise instructed, only the technician in each group may operate equipment such as this. If there are two technicians in a group, the technicians do calculations independently and then compare answers. Observes and comments on group dynamics and behavior with respect to the learning process. The reflector may be called upon to report to the group (or the entire class) about how well the group is operating (or what needs improvement), and why. Presents oral reports to the class. These reports should be as concise as possible; the instructor will normally set a time limit.

In general, we try to make each group heterogeneous with respect to both student performance and gender, as has been suggested (3). In some circumstances it may be appropriate to have the students select the groups, although we have not done this. The membership of the groups changes, frequently at first, less frequently as the semester progresses. The timing of these changes depends on the instructor. At the beginning of the year, in the absence of substantive information about relative student performance, group members are selected randomly, or in a manner that enables every student to meet and work with every other. This exposes students to a variety of learning styles and approaches. After the first exam, students may be grouped according to their performance on the exam: the highest- and lowest-scoring students plus two from the middle in one group, the second-highest- and second-lowest-scoring students with two more from the middle, etc. These groups may be maintained until the next exam, or changed more frequently, or maintained even longer, depending on the instructor’s preference and group performance. Guided Inquiry Worksheets The worksheets comprise three basic parts:2 Model, Data and/or Information. The model can be a figure, an equation, a table, text, or any combination of these. It is designed to define or develop some chemical concept. In some cases, information or data are presented as background or elaboration for a model. This component is the Exploration Phase of the learning cycle. Critical Thinking Questions (CTQs). Answers to critical thinking questions reveal fundamental relationships or concepts inherent in the model or elicit interpretation of the information. The questions are crafted to lead the student to make inferences and conclusions. These questions also provide a model for the types of questions scientists ask in an effort to understand new information. This is the Concept Invention (or Term Introduction) Phase of the learning cycle. Applications. These exercises are designed to give the students additional practice in working exercises and solving problems using the chemical concept(s) discovered through the model and the CTQs. These are homework-type problems, often including end-of-chapter problems from the textbook,

and are generally not done in class. This is the final phase of the learning cycle. Worksheets used for about 90% of the classroom content of our general chemistry course have been produced and are commercially available (7 ). Instructor’s Interaction with Groups Generally, the instructor spends most of the period moving among the groups, observing and listening to their discussions. For each group, the instructor examines the recorder’s answers to the CTQs (reading over the shoulder of the recorder). These are considered to be the official group answers. A copy of them is submitted to the instructor at the end of each period. This provides an opportunity for feedback to the group and for catching any confusion or misunderstanding that may have been missed during class. An alternative is to have the recorder write down the important concepts learned during the class, rather than the answers to the CTQs, to be submitted to the instructor. This forces students to think about what they are learning as the class proceeds. In addition, each student keeps a record of the group’s answers to the CTQs, usually writing them directly onto the worksheets. This reinforces the answers in the student’s mind and serves as a source of information when completing the Applications. If the instructor finds that students are proceeding at an adequate pace and demonstrating sufficient understanding, no intervention is needed; after staying briefly and listening to the group interaction, the instructor moves on. Occasionally a question may be posed to one of the group members to make sure that he or she understands a concept or to elicit a verbal explanation of an answer which may be correct. Some care and discretion must be used, however, as this will interfere with the group’s time and dynamics. To facilitate the overall evaluation of each student’s group participation, a small (4by 6-in.) notebook may be carried, with one page in the notebook devoted to each student in the class. If one or more of the answers to the CTQs are incorrect, the instructor must make a decision whether to intervene. There is a strong temptation to intervene, but this should be avoided if possible. Our experience is that students learn best and retain information longer if they (the group working together) discover the answer; telling the students the correct answer has little benefit. Often, students will encounter a seeming contradiction or conflict at a later point in the worksheet and thereby uncover their own error. Testing and Evaluation Every period (except the first class and the period after each hour exam) begins with a five-minute quiz. This quiz is based on material addressed during the previous class period and usually focuses on one of the key concepts developed. The purposes of the quiz are to give the instructor immediate feedback on how well the concept was learned; to reinforce the concept in the student’s mind; to encourage the student to do the Applications before the quiz is given; to partition the course material into small, manageable sections; to encourage the students to use this method of learning, rather than cramming the day (or night) before the examination; to develop good study habits. Quiz grading varies with instructor. Some quizzes are group quizzes, some individual. The reason for the group

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grading is to reinforce the idea that this is a team effort, and that it is in everyone’s best interest to ensure that all members of the group understand the material. Positive interdependence such as this is an important characteristic of successful cooperative learning (3). Students having difficulty with a concept clearly benefit from the explanations of those who have a firmer grasp of the idea. As we know from our own experience as instructors, explaining these concepts to others strengthens and solidifies the understanding of the explainer. In this way, all students in a group benefit from the group interaction. Our experience has been that at some time during the course or during an individual class meeting, every student has been either an explainer or a listener. In our courses, most of the final grade is determined by grades on hour exams, labs, and the final. The hour exams, final, and most of the laboratory reports are graded on an individual basis. This individual accountability is also important in effective cooperative learning situations (3). The laboratory component is not a separate course; laboratory performance is 20% of the overall course grade. We allocate about 10% of the overall course grade to quizzes (whether graded individually or in groups) and about 5% to group participation. A Typical Class Period A typical class period has the following components. 1. The instructor posts a list of student names, groups, and roles in a prominent location before the class period begins. Students make note of their respective groups and roles as they enter the classroom. They go to the location for their group (group 5, for example, is always at the same location in the room). 2. When the class begins, the instructor hands out the quiz for that day and gives the students five minutes for its completion. 3. The instructor collects the quizzes at the end of the five-minute period (sharply). 4. A folder containing items such as graded quizzes and recorder’s notes (with instructor comments) from the previous class period, for each member of the group, is distributed to each manager. 5. The students may be given a short time to discuss the quiz they have just taken. This may be followed by class discussion, the total amount of time typically being about two minutes. (Often, students spend a minute or so going over the quiz, even if that time is not specifically allotted.) 6. A brief (less than a minute) recap of the previous class period or introductory remarks pertaining to the day’s activities may be given. 7. Students begin working on the assigned worksheet. 8. The instructor circulates and examines the recorders’ answers to the CTQs (as previously described). 9. A variety of techniques are used to provide for interaction between groups. Sometimes students are asked to report the group answers to one or more CTQs to the entire class. This is particularly useful when students are having difficulty with a topic. Groups may also be asked to compare answers and resolve any discrepancies, or the members of a group that has completed the activity may be dispersed to the other groups to act as “advisers.” 572

10. The groups are stopped when there is about five minutes remaining in the class period. Students are given (either individually or as a group) about two minutes to write answers to a question such as: What are the two (or three) most important concepts you learned today? What was a strength of your group’s performance today? An area for improvement? What question do you still have about the material examined during class today?

Group processing such as this is another important component in effective cooperative learning activities (3). 11. The presenter may be asked to report the group answers to the questions above to the entire class.

Guided Inquiry Laboratory The laboratory follows the same guiding principles as the classroom meetings. The laboratory activities are generally performed in groups, and often the data obtained from all the groups is pooled and discussed by the entire class. Guided inquiry or discovery experiments are designed to lead students to hypothesis formation and testing (8). The student begins by collecting data and looking for trends or patterns. Ideally, a hypothesis is formed and then tested. The goal is to make connections between observation and principles. Again, this approach is based on the learning cycle, which consists of three phases: data collection, concept invention, and application. Each investigation begins with a question designed to elicit a hypothesis from the students before they begin the first phase of the study. The students then collect data to support or refute the original hypothesis. Perhaps they will need to form a new hypothesis at this stage. Finally, students are asked to apply what they have learned. An unknown may be used for this stage; in some cases a question may suffice to show the application. Guiding questions are desirable along the way to require a student to think about various steps of the investigation and not simply follow instructions.

Boiling Points of Liquids Determination of the relationship between the boiling points and structures of liquids illustrates the way a guided inquiry experiment is carried out. This experiment is performed before any discussion of intermolecular forces. It begins with the “Question of the Day”: How is the structure of a molecule related to its boiling point? The boiling points of n-octane and 2-butanol are given to the students, who are then asked to name all factors related to molecular structure that might influence the boiling point. These factors are listed for the class. Next, students are told that this project will investigate the various hypotheses suggested by the students themselves, by measuring the boiling points of various liquids. There follows a discussion of the measurement of boiling point by a simple distillation apparatus. Each group of students, usually about four, is then given a list of several compounds and asked to predict the boiling point of each of their compounds and to advance a hypothesis on which they have based their predictions. After the group has the correct structures for all of the compounds and have developed a hypothesis and predicted boiling points, each member of the group distills one of the liquids to purify it and obtain its boiling point.



All the boiling point data are collected and presented to the class. Each group determines whether their hypothesis is supported or refuted by their own data. Then each hypothesis is tested by using all the class data, and new interpretations are made. Almost all groups will suggest that molecular weight is important for determining the boiling point and the data collected will clearly support this. However, when class data are pooled it becomes apparent that molecular weight is insufficient to explain all the data. For example, the molecular weights of acetone and 1-propanol are about the same but there is a difference of almost 30° in their boiling points. This discussion of class data can go on for about as long as desired because such a wealth of information can be gleaned from these data. We use molecular modeling calculations to find dipole moments and to calculate partial charges on atoms of the molecular species considered. This enables students to find the hydrogen bond and dipolar interactions responsible for discrepant behavior. The results can then be used to let students discover the role of intermolecular forces in the determination of boiling points. We are indebted to the College of the Holy Cross, another member of the New Traditions consortium, for the concepts used to develop this experiment (9). Assessment of Guided Inquiry Instruction We are in the process of completing a first assessment of this approach to general chemistry. We are just now attaining a sufficiently large number of students who have experienced a full year of guided inquiry in general chemistry and gone on to organic chemistry to permit a statistical assessment. However, we have some results for a few measures. As can be seen in Table 1, the sections taught according to the principles of guided inquiry have experienced a decrease in the W, D, F rate from 21.9% (420 students, Fall 1990–Spring 1994) to 9.6% (438 students, Fall 1994–Fall 1997).3 In the Guided Inquiry (GI) sections, the withdrawal rate is 2.3% and only 1 out of 438 students has received a grade of F in these sections. In contrast, students taught by these same instructors previously had a W rate of 9.3% and 3.6% failed. Final exams given to the GI students that were substantially similar to exams given in the past showed that GI students scored as high as or higher than students who had taken a more traditional course from the same instructor. Preliminary analysis of student performance in the subsequent organic chemistry sequence (taught in a fairly traditional style) indicates that the GI students perform as well in organic chemistry as the authors’ general chemistry students did prior to implementation of the GI approach. A full analysis will be undertaken after the end of the 1997–98 academic year. Students have an extremely positive attitude toward this approach. A short questionnaire was distributed to the 96 students enrolled in GI sections of CHM 112 (the second semester of General Chemistry) at the end of the Spring 1996 semester. Only 26 of these had been enrolled in a GI section the previous semester. One of the items on the questionnaire was “Describe at least one strength of this course.” Half of the students (48) mentioned the use of groups in promoting learning and understanding, and an additional 21 specifically commented that the course was better for learning than a traditional approach. When given the opportunity to make “any other comments”, 31 students indicated that they

Table 1. Grade Distribution for Authors' Sections of General Chemistr y Period

n

Percentage of Students Earning Grade A

B

C

D

W

F

D+W+F

F90–S94

42 0

19.3

33.1

25.7

9.0

9.3

3. 6

21.9

F94–F97

438

24.2

40.6

25.6

7.1

2.3

0.2

9.6

thought this was a good approach to teaching chemistry. Two typical comments were:4 I really enjoyed this way of learning in groups. I found it to be very beneficial. I retained more of the information in this course than in all of my other courses. It forces everyone in the class to have an active part in every class. We never just sit here and listen to a professor talk. We are actually doing something. I have learned (and can remember what I’ve learned) significantly more this semester than last and I feel the group learning method is an excellent method of learning.

For Spring 1997, first-semester GI students were given the opportunity to reenroll in a GI section for CHM 112 rather than go through the regular registration process, which involves some uncertainty in which section a student will be assigned; every student from a first semester GI section who intended to take the second-semester course elected to stay with the GI approach. Conclusions We have found that it is possible to implement a guided inquiry general chemistry course following the philosophical and pedagogic principles of the learning cycle and cooperative learning. We have found that we are able to hold the students responsible for roughly the same quantity of content as we did in our previous mode of instruction. The percentage of students successfully completing the course is substantially increased using this approach. We believe this to be the case because students who are active and involved in a classroom setting find it difficult not to learn something. Preliminary assessment of their achievement in traditional future courses indicates that it is roughly the same as when more traditional techniques were used. We have yet to discern negatives about this approach that would lead us to abandon it. Acknowledgments We gratefully acknowledge the financial assistance of the New Traditions Systemic Initiative funded by the National Science Foundation and the Fund for the Improvement of Postsecondary Education of the U.S. Department of Education (P116B40949) for support of the development of laboratory experiments associated with this project. Many thanks are also due the many members of the Middle Atlantic Discovery Chemistry Project, who provided both valuable discussions and helpful support for our work. Notes 1. Pacific Crest Faculty Development Workshop by Pacific Crest Software, Corvallis, OR. 2. The original model for our materials comes from Apple, D.; Beyerlein, S.; Schlesinger, M. Learning Through Problem Solving. Pacific Crest Software: Corvallis, OR, 1992.

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Research: Science and Education 3. For each set of years, the data refer only to those students taught by the authors. Thus, the “control group” consists of students taught by us before implementation of the guided inquiry approach. 4. The categorization of student remarks and the selection of representative student quotes were done by a student who had taken the course in a previous year, and not by any of us.

Literature Cited 1. Spencer, J. N. J. Chem. Educ. 1999, 76, 566–569. 2. Bonwell, C. C.; Eison, J. A. Active Learning: Creating Excitement in the Classroom. ASHE-ERIC Higher Education Report No. 1; The George Washington University, School of Education and Human Development: Washington, DC, 1991.

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3. Johnson, D. W.; Johnson, R. T.; Smith, K. A. Active Learning: Cooperation in the College Classroom; Interaction Book Company: Edina, MN, 1991. 4. Cooperative Learning: Theory and Research; Sharan, S., Ed.; Praeger: New York, 1990. 5. Bruffee, K. A. Collaborative Learning; Johns Hopkins University Press: Baltimore, 1993. 6. Slavin, R. E. Collaborative Learning; Johns Hopkins University Press: Baltimore, 1983. 7. Moog, R. S.; Farrell, J. J. Chemistry: A Guided Inquiry; Wiley: New York, 1997. 8. Ditzler, M. A.; Ricci, R. W. J. Chem. Educ. 1994, 71, 685. 9. Discovery Chemistry Instructor’s Manual, Department of Chemistry, College of the Holy Cross: Worcester, MA, 1994.


A Guided-Inquiry General Chemistry Course - Journal of Chemical

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