Evolution of an Integrated College Freshman Curriculum Using Educational Research Findings as a Guide Fred Garafalo and Vin ~ o ~ r e s t i ' Massachusetts College of Pharmacy and Allied Health Sciences, 179 Longwood Avenue, Boston, MA 02115 At one time or another, most instructors in the natural sciences reflect upon the expectations they have of their introductory courses. These may include transmitting essential characteristics of their particular discipline, connecting the subject matter to environmental, social, and philosophical issues, and serving as a foundation for further study in the field for some students, while also serving as an appropriate terminal course for others (1).Creating a course that meets these expectations is a tall order that is complicated by several factors. These factors conspire to create what might be called the instructor's dilemma, depicted in Figure 1. The information explosion currently occurring in all areas of knowledge can tempt instructors to add more material to their courses in order to-keep them current. By contrast, research in education suggests that instructors actually should be teaching fewer topics in more depth, and promoting active learning. In addition, boundaries among the traditional disciplines of biology, chemistry, and physics are disappearing, suggesting that instructors should be making the effort to point out relationships between their discipline and others. Finally, since instructors often encounter a diverse population of learners, they also must he concerned with finding an appropriate level for their presentations. One or more of these factors can serve as a catalyst for instructors to initiate some type ~.of course or curriculum
restructuring. In our case, frustration with trying to cram too much information, particularly in biology, and the desire to elucidate connections among the natural sciences for our students and ourselves, precipitated the decision to integrate freshman chemistry and biology six years ago (2).This report gives an overview of the evolution of our integrated cumculum from academic year 1986-1987 to AY 1991-1992, and the impact that research in teaching and learning has had on our attempts to deal more effectively with the instructor's dilemma.
Background and Initial Efforts Freshman chemistry at the Massachusetts College of Pharmacy and Allied Health Sciences comprises a threequarter sequence of four-credit courses, with laboratory limited to quarters two and three. Freshman biology comprises one quarter of general and one quarter of animal biology, each with a laboratory and each worth five credits. Chemistry is offered by the Department of Chemistry, Physics, and Mathematics, comprising 11 individuals, while biology is offered by the Department of Pharmacology, Biology, and Toxicology, comprising six individuals. The college is a private institution with about 1100 students, 70 faculty, and a small graduate program in the pharmaceutical sciences. The initial freshman class size has averaged about 115 students in recent years. The majority of these are pharmacy majors, with a few chemistry, medical technology, and health ps~chologymajors as well. Almost all students 'Present address: Wheelock College, 200 The Riverway, 6oston, have taken hich school chemistry and biolom. but their MA02215. backgr'unds vary~%ombined SAT scores often range from 700 to 1300. While the freshman class for AY 1991-1992 had a "B" j Information Explosion j overall high school average, :.......................................................... : their average verbal and mathe(Always More Material From Which to Choose) matics SAT scores were only 409 and 497, respectively. ~ h e s are i close to the national average for all students taking the SATs. The idea for curriculum integration arose from our work in a team-taught, upper-class elective course called "Perspectives i n Natural Science," that we have been teaching for nine Promote Active Learning) years (3).The effort involved in presentation, creating this course has made us more aware of the unifying themes in scientific descriptions of nature, and their potential to sewe as points of integration for our freshman curriculum. "Perspectives" continues to serve as a (Elucidate Connections) testing ground for materials that, in part, become incor~orated into freshman chemistry Figure 1. The instructor's dilemma. and biology. 352
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We began the freshman integration project by examining tooic oresentation and conceot develooment in both courses to fmd places where students would benefit from the introduction of physical and chemical principles in chemistry, before their application in biology. We found many places where ideas would flow naturally from the physical into the biological sciences, where they could be reinforced. We concluded that it was possible to integrate material without compromising the identity of either course, and that we couid use the-integration encourage students to see relationshios amone the traditional disciplines. We decided to coordinate the presentation of topics using the concept of energy transformation as the primary integrating theme (2). The initial approach to integration also included starting with tangible examples to introduce concepts before describing their applications in less familiar areas, and presenting mostly qualitative material in quarter one of chemistly. We hoped that pose poning quantitative treatments would enable weaker students to improve their mathematics skills in an introductory course taken concurrentlywith the first quarter of the integrated curriculum. The cumculum evolved in several ways over the next few years. Attending each other's classes, extensively in the first year and sporadically thereafter, gave us the opportunity to discover new points of integration and ways to reorganize topic sequences. We found that as we placed more emphasis on qualitative understanding, we had to remove more material. This led to increased efforts in creating our own handouts, and placing less emphasis on textbook presentations. Although we were encouraged by positive student evaluations of the integrated cumculum after its first full year (4), problems became evident as we continued soliciting feedback and following student performance on examinations. While coordinating the presentation in chemistry with that in biolow had oroven useful. our emectations about the volume-if makrial that students were able to assimilate in the latter course turned out to be unrealistic. The initial overviews of physical concepts that we presented were, in retrospect, too crammed and too frequently amounted to precondtructed versions of the innt&tor9s knowledee. Philosoohical dieressions. inserted with the goal of making the bresentazons more interesting, oRen ied to confusi& and wild misconceptions on thepart of some students. Finallv., the diversitv of student backmounds maenified the issue of appropriate level of presencation, and ;ealistic assessmentif concept mastery. ARer two vears it became obvious that we were havine onlv " limited success reaching the more poorly prepared. While experience had convinced us of the benefits of introducing students to physical concepts through qualitative treatments, eliminating calculations almost entirely from the first quarter of chemistry did not help poorer students once we engaged them in quantitative problem solving in quarter two. In addition, most students, including many of the better ones, did not perform wen when tested on material that demanded demonstration of concept mastery. Evolution accelerated aRer we became aware ofresearch findings in the area of teaching and learning through our participation in Chautauqua short courses for college teachers (5,6). This allowed us to compare our own efforts with a formal body of information that had been accumulating for about 20 years, and led to more radical changes in our curriculum structure. A brief summary of these research findings will elucidate our rationale for adopting specificapproaches that complement our own.
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Research Findings First, research suggests that learners construct their understanding, linkingnew ideas to what they already know. They do not simply mirmr what they read or are told (7). Conseauentlv, students are likely to hold on to preconceptions 4 deviiop misconceptions in their interpretations bf natural phenomena and the svmbolic representations used to describe physical situations. Misconceptions in understanding have been discovered in physics, rhemistry, hiology, and mathematirs students (7-22). They appear reeardless of the student's level of reasoning, arc resistant to change, and persist even i n studentdwho do well in courses that stress quantitative calculations (7,8,23,24). Second, lecturing to students is not an ideal way to transmit knowledge. Traditional passive lecture format does not encouraee students to discover misconceotions. and make unifying connections (25). Tobias describes stud: ies in which college faculty in the arts provided feedback on lectures presented by a physicist colleague (26). Participants wanted to ask more questions but the format did not allow enough time, had no framework of prior knowledee to facilitate auestion framine. were not able to order t h i information, and felt that therkcturer had no sense of the kind of misunderstaudina that was occurring. Third, unfamiliarity with t&hnical vocabuln& is a definite source ofdificultv in uuantitative prohlem rolvine fur students who can c o n s k t beginning students (f7). and manivulate algebraic expressions for problems involving famiGar conceits have dficulty formulating equivalent expressions when the concepts are unfamiliar. Unless students are required to extra& explanations and interpretations of the underlying phenomena in their own words, they memorlze formulas or patterns for petioming calculations(28,. Luc~dexplanations from trachws and Instruction in expert problem-solving techniques have proved to be of little value in helping students to become better problem solvers (29). Fourth, the organization of knowledge imparted in teachine is as irnoortant as the knowledee itself (30.31). ~x~erts-store kniwledge in "conceptual ~hunksX-clukters of information related bv a fundamental concept or principle (32). Each concept i s defined by many featires and relationships built up by using the concept many times and in many different situations. By contrast, students'conceptual knowledge - lacks coherence. When they attempt to apply concepts, students usually retrieve miscellaneous fragments of knowledge, cannot interpret definitions, and have no way to resolve inconsistencies. Spiro suggests that a aualitatively different type of understanding than that r&red for recognition and recall is necessariin order to grasp interrelatiomhipn among concepm and apply knowledge to differing circumstances (33,. Topic sequencing in traditional courses and textbooks usually does not encourage students to organize knowledge amund important roncepts and to recognize how such concepts arc interrelated. &l of these findings suggest that students should be provided with an environment that allows time for them to exulore conceots in a varietv of situations so that thev mav understkding for themselves. WhUileinco~struct tuition directed our initial work toward aooroaches consistent with the frst and fourth fmdings, webere able to develop a more comprehensive approach to curriculum development aRer becoming aware of the problems associated with the second and third findings and the approaches available for dealing with them.
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Response to Research Findings Curriculum Content
Figure 2 indicates the six major themes around which our curriculum is integrated currently. In the center of the Volume 70 Number 5 Mav 1993
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Chem Topics
0
Bio Topics
I I
Macromolecules
Geomet and Sol,
cellular &uctures
I
Matter Transformation Stoichiometry
Self-Organization
Ecosystem Cycles PRIMITIVE CONCEPTS Quantity, Extension, Duration OPERATIONAL DEFINITIONS Descriptors for Change
Membrane Potentrals Energy Transformation Grad~ents
Equilibrium Figure 2. Themes around which the curriculum is integrated and the topics they comprise hexagon are the most fundamental ideas from which the others emerge. The topics comprising each theme are introduced in a qualitative fashion, usually in chemistry, and then reinforced as they are applied in biology. This helps to elucidate the defining features of concepts and improves the chances that they will be recognized as essential to understanding biological processes. All topics in a given theme are not presented at the same time. There is movement back and forth throughout the year among the themes as students are encouraged to organize their knowledge around them. A list of general topics in each course and the approximate number of class meetings devoted to exploring them is presented in the table. We have steadily reduced the number of specific topics to allow more time for those that remain. ChemisCry topics that have been deemphasized or removed include quantum numbers, electron configurations, orbitals, and detailed descriptive chemistry of the elements. Recent literature suggests that these are all likely candidates for reduced emphasis (3438). Consequently, more time is devoted to stoichiometry, energy transformations, and qualitative solution chemistry. Since general biology is limited to one quarter, severe time constraints forced serious decisions about its content. Detailed plant anatomy and comparative animal physiology have been eliminated, while emphasis on the role of different organisms and their interrelationships in transforming matter and energy has increased. This also has allowed for a formal introduction to biological information. In quarter two of biology, the focus has shifbd away kom the anatomy and physiology of human organ systems, and toward cooperative interactions of animal cells and tissues.
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Presentation Our presentation has evolved toward a more epistemological one that seeks to guide students from observed phenomena and operational defdtions, to reasonable inferences and deductions, and only then to models and theories. Arons has found that students respond favorably to this approach and are more willing to tolerate the frustration and effort they must make to gain control of new ideas (23). Quarter one of chemistrv follows the develo~mentof ideas in stoichiometry andatomic structure in'approximate historical order. Atoms are not introduced until week two, while electrons, atomic numbers, and isotopes do not appear until weeks five, six, and nine, respectively, This approach is consistent with the philosophy of Bent (39) and attempts to give students a clearer picture of the problems explored by scientists at particular times in history. Some time is spent considering the historical development of the first law of thermodynamics, but no effort is made to trace the history of concepts like mass or force. Instead, such concepts are introduced thmugh operational definitions whose utility in describing and predicting phenomena is then demonstrated. Material in quarters two and three elaborates upon that of quarter one, but the development is not strictly historical. Topics in biology are coordinated with those in chemistry but with no attempt at historically ordering them. The topdown approach, starting with organisms and ecosystems, is consistent with that used in chemistry. Since many integrating themes are introduced in chemistry, we feel ihat it is important for students to avoid viewing the study of biology as merely applied chemistryand physics. Therefore,
Integrated Currlculurn Course Hours
Prlnclples of Bio
GenwaI Chem 1 Counting, Measuring 3 Proportional Reasoning Overview: Mass. Force 5 Energy lntm to Stoichiometry: History Periodicity1Atomic Structure Bonding and Geometry Overview: Energetics, Gradients, Equilibrium, Rates Stoichiometry II
7
Nucleus1 Element Formation
4
6 6
5
6
Pmperties of 3 organisms Levels of Organization 2 Taxonomic Classification Natural Selection 3 Principles of Ecology1 6 Matter Cycles Biomolecules 5 Biological Membranes 2 Cell Structure /Organelles Transport Pmcesses
4
Bioenergetics Information EncodingIFeedback Information Classical Genetics
6
3
3
5
Anlmal Cell Biology
General Chem 2 Colligative Properties
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Stoichiometry I l l
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Gases
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Equilibrium
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Solution Chemistry 1: Acids, Bases, Salts
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Redox Processes
8
General Chem 3 Symbolic Representation of Change Energy Considerations1 Spontaneity Kinetics
6
Solution Chemistw 11
7
16 5
3 GeneticdCell Differentiation TissueslEpithelial 4 SheetsISkin Connective Tissues 2 Calcium Homeostasis Molecular 4 MotordMuscles Membrane 6 PotentialdNeumns and Synapses Neuronal 4 CircuitsIFeedback lntro to Signal Transduction
Cardiovascular 7 Systems /Pressure, Flow, Resistance Respiratory Exchange 3 SurfacedGas Laws Gi Exchange
SurfacedNutrient Homeostasis Excretory Surfaced Polarized Epithelial Cells
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3
Coordination Chemistry 4 Hours include the weekly noncredit recitations that we now use as regular class meeting hours. an effort igmade to stress certain ideas that are not totally unique to biology but are sufficiently different fmm those emphasized i n chemistry to warrant special attention. These properties include autopoiesis, system properties, and self organization. Topics are spread out over time, so that students cycle back and experience ideas in a progressively richer con-
text, as suggested by Arons (40). This occurs within each course. and also between them. For example, colligative proper;ies are first introduced in chemistry-during aqualitative overview of aadients and equihbrium in quarter one. Quantitative ckculations reinforce the concepts in quarter two. Later in quarters two and three, colligative properties are revisited during discussions of LeChhtelier's principle and are used to provide experimental evidence for the existence of ions in solution and the rationale for possible coordination numbers of metals. Quarter-one biology topics like gradients, protein conformation, and feedback information are developed in quarter-two discussions of membrane potentials, muscle contraction, and the coordinated functioning of various animal tissue types. Qualitative overviews in chemistry of energetics, gradients and equilibrium, anticipate discussions based on these ideas in biology. In general, topic sequencing in our curriculum represents a careful synthesis of epistemology, intuitive concept development, and coordination of topics between the two courses. Many other sequences could be envisioned and would depend upon the particular themes and topics emphasized by an instructor. Constructing Knowledge Since researchers have found that it is essential for students to be able to relate new material to what they already know (7,4143), we try to encourage this by gearing our presentation toward students constructing their own understanding, and not toward the instructor's previously constructed version of the knowledge (44). Initially, in chemistry, we ask students to reflect on how the fundamental ideas of quantity, extension, and duration give rise to the concept of magnitude and the activity of creating numbered scales for the process of measurement. Students then work with data sets obtained from simple examples to construct operational definitions of basic concepts including area, acceleration, mass, and force. We encourage them to see that such concepts are useful creations rather than discovered truths. Although some early material is similar to that covered in introductory physics courses, the emphasis is not exactly the same. For example, no effort is made to continue into equations of motion, while we stress learning to distinguish between forces (passive versus active, and contact versus noneontact), and interpreting change in terms of energy transformations. At this point in the cumiculum, the goal is to give students a chance to master vocabulary, practice lines of reasoning, and absorb basic concepts so that they can be applied critically throughout the remainder of both courses. We only deal with average rates of change in this overview, postponing discussions of the subtleties associated with the idea of instantaneous quantities until quarter three. At that time, we use Zeno's paradoxes as a way of engaging students in discussions about the pitfalls inherent in descriptions of change. This reduces coverage of other topics, but we are convinced that the time is better spent in helping students grapple with the difficulties involved in creating symbolic representations and intmducing them to applications in simple physical systems. We are using this approach to encourage more of them to go on to calculus. Our initial engagement in biology asks students to refled on obsewable properties of living systems before considering complex ideas like dynamic homeostasis (45). Students are challenged to examine the differences between the apparent order exhibited by a 20-year-oldperson and a marble sculpture thereof and asked to define the parameters by which the two might maintain their appearance Volume 70 Number 5 May 1993
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over a five-year period. The idea of dynamic order via continual re-creation of structure and exchange of matter with the environment (autopoiesis) (46) is thereby introduced and becomes the thread that ties the bioloev seauence together. E n e m flow is first encountered in ecosvstems. Cellular metab&m comes later. When we make the transition to the molecular level. we maintain a connection to the macroscopic world by discussing energy utilization in changing the shape of proteins and the ultimate effect this has on generation of motion in cells. The idea of information arises a t the end of quarter one, initially via discussions of common experiences such as language and music, and subsequently in conjunction with the topic of genetics. This segment ofbiology also serves as an introduction to system properties and self organization, which are then developed qualitatively over the entire second quarter of biology systhrough - discussions of animal feedback rewlatory terns.
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Critical Thinking
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In the uast two vears. we have beeun creatine an mvironment where concept presentation is formally coupled to the development of critical thinking skills as suggested by Lagowski and Pavelich (47, 48,.Such skills arc described by Amns as processes that underlie analysis and inquiry (49), and include deductive reasoning, distinguishing between observations and inferences, formulating - hypothe.ses, interpreting data, and proportional reasoning. The introduction to stoicbiometry presents students with the opportunity to work on all of these skills. We begin qualitatively by introducing basic ideas about change and substances. Students work in pairs interpreting and predicting results in exercises de- experimental signed to assist them in clarifying terms like element, campound, a n d mixture. By posing hypotheses about observations associated with the heating of a metal in air, we encourage students to recognize the utility and importance of mais measurements. We encouragethem to'discover" the laws of delinite and multiple proportions hy interuretine the results of chemical analvsis data. Next, students must work with data on multiple combining masses and the competing hypotheses ofearly 19th century scientists (Dalton's rule of simplicity a n d Avogad;o3s hypothesis), to deduce and comp&e relative atomic masses of elements and molecular formnlas of compounds. This finally leads to Cannizzaro's method of determining formulas and atomic masses. These activities are the focus of seven class meetings. By postponing topics like atomic structure that typically are found in the earlv Dart of a chemistrv curriculum. we focus stndents' attention on what couli be determined a t that time in historv. ". based on the available evidence. At this point in the course, students do not even have access to a periodic chart. In biology, we use the format of Statkiewicz and Allen (50) to create multiple-choice questions for graded homework assignments in which stndents must analyze incorrect as well as correct choices. By interpreting biomass data, for example, stndents are expected to test hypotheses concerning energy flow through mini-ecosystems comprising different combinations of organisms. In addition, numerous case studies have been develoued that students read alone or with a partner. These either present significant experimental results in simplified form, or give examples of situations where important concepts arise. The former type introduces students to research findings, asking them to frame observations into explanatory hypotheses, or describe how new findings challenge an existing hypothesis. In the latter type, discussion questions direct stu-
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Journal of Chemical Education
dents to extract the important concepts from details of a soecific situation. For examole.. the basic urincioles underlying cell to cell communication can be discovered through suecific case studies involving the nervous svstem. hormones, or blood cells of anim&s. In this type or case study, students are exulicitlv instructed not to memorize details. Such case studies oken illustrate the problem of describing dynamic systems with a language &hose terminology is static. For example, after students read and discuss examples of symbiotic relationships among organisms, the terminology describing such relationships (mutualism, parasitism, etc.) is formalized. Students are then asked to decide which symbiotic relationship is illustrated by each case studv and to exulain their reasonine. In several cases. the relationships between the partner organisms are context deoendent. Certain eut bacteria. for instance., mav " be described as parasites in animals with a depressed immune system, hut as mutualists in animals with an intact immune response. Some of the case studies also can be reanalvzed a t several uoints within the course. assisting students in tying together ideas. For example, manycase studies on svmbiosis also illustrate princiules of feedback communication. Curriculum integration has provided benefits by allowine us to draw on each other's exoeriences in develooine types of questions to pose to stndents. For example, we found that auestions on internretine exuerimental results. that had been used more f;eque$ly in biology than id chemistry, can help stndents understand the lines of reasoning that led to the atomic masses of the elements, or the nuclear model of the atom. Such questioning allows for a more meaningful encounter with a topic like atomic structure than, for instance, asking students to reproduce electron configurations. Conversely, recognizing that students must be grounded f m l y in proportional reasoning with physical concepts has helped us decide when it is appropriate to give questions involving such reasoning in biology.
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Active Learning Although we still do some formal lecturing, particularly in biology, the curriculum is evolving toward a discussionbased format. For the past two years, we have used the Gutenberg method (25), where students are expected to complete reading assignments prior to coming to class, and then participate in instructor-led classroom discussions to clarify their understanding. In chemistry, approximately 30 min of each hour are snent in this wav.. while less time is devoted in biology classes. This technique has been used successfullv in classes with uo to 100 students 125,. and we keeps have found that a core of 10-15 active the sessions lively. Calling on students encourages sporadic participation by many others. The Thinking-Aloud Pair-Problem-Solving Method (TAPPS),also has been used in chemistry for the past two years and during the past year in biology (6). Using this techniaue. each student in a uair takes turns readine a problelh A d thinking aloud as'he or she attempts to szve it. The partner, called the listener, does not convey information, but tries to follow the solver's line of reasoning, asking for clarification when necessary. The listener's main task is to keep the solver talking. In this way, the solver activelv . exoeriences anv difiiculties he or she mav be having in attempting to cohtruct a solution. It is mo& important to verbalize the route to the answer than to get the correct answer. This approach is consistent with findings suggesting that students take more of an interest in learning when they receive rapid feedback on how they are doing (51)and has been used successfully with students who have poorly4eveloped reasoning skills (6).
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We use TAPPS several times each week in approximately 20-min sessions. During the initial sessions, two or three instructors or tutors circulate throueh the room. determining if the pairs are using the methid correctly: Although some students resist its use throughout the year, most embrace TAPPS within a few weeks, and after the first auarter. the maioritv of students prefer it to traditional; passi;e problek-so&ing sessions: The method also is used extensively during chemistry office hours, where students solve and the instructor listens (6).This has been an eye-opening experience. Frequently it takes poorly-prepared students, guided by an appropriate line of questloning, up to 20 minutes just to formulate a clear picture of what an intermediate-level problem is asking. Discussion Impact of Integration on Teaching Philosophy
Our integration efforts have led directly to major changes in the way we now structure each course. The decision to introduce concepts like energy through discussions of macroscopic objects in familiar circumstances meant delaying discussions of molecules and bonding in chemistry. This in turn led to the development of the topdown approach in biology. Engaging students with material that deals with tangible ecological examples has been valuable in easing them into the biology course, and introducine them to oroblem-solvine activities. However. while a traditional piesentation of biology progresses linearly from atoms, to molecules, to organelles, to cells, and beyond, a discontinuity occurs in the top-down approach when eoine from the macrosco~icto the microscodc world. bstu&&ng biology around themes like autopoiesis, so that the presentation would better convey a sense of internal continuity, has been a direct result of curriculum integration. As each of us pursued our own avenues of curriculum development, str& began to appear in a number of places where we felt that material had once been well coordinated between the twocoursen. For example, as the historical approach took hold in chemistry, the early introduction of material on molecular structure became less desirable. This situation, coupled with the need to provide more time earlv in auarter one for students to hone their skills in proportionai reasoning, disrupted the once-coordinated p ~ sentation of material on molecular structure in chemistry and protein structure in biology. As we have come to embrace the ideas of students constructing their own understanding, and of cycling back to ideas for progressively more detailed development, such tensions between the courses have diminished. Because topics now recur several times, we no longer feel compelled to cover a given topic completely in one course before it is introduced in the other, and have become more comfortable with the fact that different students may construct their understanding of a particular concept at different times.
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Teaching Materials
Academic year 1990-1991 was the first time we relied com~letelvon our own handouts. which reflect more accurateiy than conventional textbooks the concept development, integration, and active learning that students experience in our curriculum. The handouts perform several functions: presenting factual data or defining basic concepts; describing measurement procedures that often serve to defme concepts operationally; discussing svmbolic representations and maihematicai &anipula
