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4 Impediments to Implementing Curricular Change: Texts, Tests, and Classroom Practice Although the committee is concerned about life-sciences education in grades K-12, the focus of this chapter is the high-school level, because this is where the most information has been gathered. Many, but not all, of the recommendations we provide for reform at the high-school level are also applicable at the elementary- and middle-school levels. TEXTBOOKS The Present Situation With estimates that 75% of classroom time and 90% of homework time involve the use of textbooks (Blystone, 1989), it is perhaps surprising that deficiencies in textbooks have not been blamed more for the perceived problems in high-school biology. Nevertheless, there are criticisms aplenty, and the very diversity of their sources has become part of the problem. Criticisms have come from biologists. Several analyses, either anecdotal (Gould, 1987; Paul, 1987) or focused on a specific topic, such as genetics (Cho et al., 1985), have graphically demonstrated how inaccuracies and confusion are perpetuated by textbooks. Textbooks have also been criticized by persons who perceive a challenge to their religious, social, or political views in the treatment of evolution or human behavior. Publishers' attempts to placate religious critics have generated still further negative reaction from biologists. Are high-school texts truly useful to students and to teachers? Students are discouraged by the overwhelming amount of material and the relentless onslaught of technical vocabulary. The task of learning becomes a treadmill, a daily but endless routine with no useful goals and little sense of accomplishment. 27
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28 FULFILLING THE PROMISE Teachers often have to spend time decoding the texts a job made more difficult by incomplete explanations and factual inaccuracies. Many students have to rely on their texts, with little guidance from their teachers. Are the present texts capable of sustaining students with little help from instructors? How might we recognize good textbooks? Biology textbooks are in- creasingly similar, but too little attention is paid to educationally desirable characteristics. When individual textbooks are reviewed, they are usually com- pared with each other, rather than with some standard (see, for example, AAAS, 1988~; and the general approach, clarity, accuracy, conceptualization, and flow are rarely considered. Criteria for evaluating textbooks have been stated in many forms (see Subcommittee on Instructional Materials and Publications 1957), but there is general agreement on the following seven needs. Although we are not aware of a thorough recent review based on these criteria, we believe that current texts fail in many respects to meet them. Adequate but not encyclopedic coverage. Concern about the deliberate omission of such central subjects as evolution and human sexuality is justified, but many current textbooks were written with a compulsion to cover exhaustive lists of terms and topics. The attempt to mention everything with or without adequate explanations is a common deficiency of present texts. Its origin is the publishers' correct perception that the current market demands it. · Factual accuracy. This fundamental criterion is often violated. Inac- curacy causes problems for students and teachers alike and raises concern about the qualifications of the authors or the care in preparing the book. · Incorporation of current conceptual understanding and new subject matter. Many publishers add current experimental advances to their texts, often set off in special boxes. But current conceptual understanding generally is not incorporated into the deeper structure of a book and in the specific explanations. Wrong impressions are given. Modern understanding generally simplifies science, rather than complicating it. Good examples are the combina- tion of cytogenetics with formal genetics and, more recently, the use of markers based on DNA structure in genetic linkage analysis. Such subjects are usually taught separately; as a result, the student fails to benefit from the simplifying combination of fields. · Logical coherence. Books written by single authors usually have a logical coherence; multiauthor books often seem like compendia of separate and disconnected segments. If we expect a student to gain increasing mastery of a subject, the subject must unfold with appropriate reference to earlier parts and repetition of older themes. A textbook should be readable and interesting. That is the hardest trait to define and judge, but a common reaction of a knowledgeable person perusing textbooks for the first time is that most fail badly in presenting a coherent point of view and vision of a given subject. The failure is communicated to students, who are understandably bored. · Clarity in explanation and electiveness of illustrations. Textbook publishers have emphasized illustration, and the amount and elaborateness of
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TEXTS, TESTS, AND CLASSROOM PRACTICE 29 illustrated material have increased faster than the number of words in the text. Yet many illustrations are mere decorations-they convey no information, they are often poorly integrated into the text, and they fail to explain. · Appropriateness to students' level and interest. "Appropriateness" has usually been interpreted as not overestimating the students' interests, reading abilities, and capacities for higher thinking, with little thought about positive educational goals, such as understanding of the material. As a result, most texts emphasize rote learning of an alien vocabulary without regard for the likelihood of understanding. As texts have grown in size, the numbers of subjects mentioned have also increased. To make their textbooks suitable for students, publishers should emphasize the teaching of a few important concepts and attend to such pedagogical elements of writing as the proper definition and economical use of terms, the appropriate repetition of important concepts, and the integration of text with laboratory exercises. · Representation of biology as an experimental subject. Textbooks should explicitly convey to students that the information presented is the result of experimentation and that understanding is constantly being refined and is must yield. subject to change as new experiments are conducted. Textbooks should also describe the nature of experimentation. To what extent is the poor achievement of our students in biology a reflection of poor explanations in biology textbooks? Textbooks are only part of a much larger problem, but the lack of sound conceptual bases, the annoying and propagated errors, and the almanac-like organization of material all suggest that the authors' own level of understanding is insufficient to permit effective presentation. Books need to convey a vision. Furthermore, biology has matured as a discipline, and it is not possible to add new subjects, such as molecular and cell biology, and keep the level of detail on traditional subjects, such as systematics. Similarly, if one wants to teach ecology as a quantitative subject, other subjects The effort by publishers to mention every subject aimed at satisfying every conceivable textbook adoption committee has produced books that do not reflect a satisfactory understanding of any subject. The effect is to introduce numerous barely defined terms, many of which are redundant, imprecise, archaic, and not often used by practicing biologists. To select an arbitrary example, how many scientists now know or care about the specific terms used to identify the morphological stages of meiosis? What is essential is the nature of the processes that are occurring. Similarly, important distinctions can be drawn between endocytosis, pinocytosis, and phagocytosis, but students would be better served by a topological understanding of the cellular traffic of membrane-bound organelles than by memorizing these distinctions. The most serious deficit in current textbooks is their authors' lack of conceptual understanding of their discipline. Biology now has much of the elegance of classical physics. At the level of the cell, common mechanisms are at work in signaling across cell membranes, in organizing the structure of the
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30 FULFILLING THE PROMISE cell in cell division or in causing the cell to move, in converting the energy of sunlight into sugars or in the oxidative metabolism of glucose, and in regulating genes in either bacteria or humans. Variation and selection are at work not only in evolution, but in the immune system. Evolution has left its footprints in the structure of DNA and in the strategies of development, and these concepts are important not only in bolstering our understanding of evolution, as introduced by Darwin, but in shedding light on human biology. The presentation of biology as an experimental subject goes beyond the textbook into the whole curriculum and in particular to laboratory exercises. There is clearly a tension between the demands for textbook comprehensiveness and the limitations of textbook size. The usual casualty is the presentation of biology as an experimental science. In that respect, the books merely amplify the growing pressures of tests and curricula to de-emphasize the process of discovery and to portray biology as the worst kind of literature-all characters and no story. In summary, current biology textbooks are an important part of the failed biology curriculum. They are often not selective in what they present and lack both a broad conceptual basis and a refined understanding of specific subjects. They emphasize memorization of technical terms. They have many misleading and superfluous illustrations. The books are different, but a tendency toward uniformity and mediocrity can be seen in recent years. Forces That Shape Textbooks The open and competitive American marketplace for books might seem to be a guarantee against mediocrity in biology textbooks. Nothing could be further from the truth. In her book A Conspiracy of Good Intentions, Harriet Tyson-Bernstein (1988) has lucidly described the interplay of interests at work in the generation of textbooks for public schools. The publishers assert that to survive in the market they must compete effectively in the large "adoption states" notably California (primary schools only) and Texas that periodically approve texts for use in their classrooms. Playing on the notion that textbooks, even science textbooks, should conform to local social and religious values, small groups have been able to dictate changes in the content of books before state approval. That phenomenon achieved prominence a few years ago in the case of the treatment of evolution, and recent events in California have demonstrated that it is still alive. Moreover, we are likely to see it in other guises as efforts to teach young children more about human reproduction increase and as animal-rights activists increase their public presence. Influences from outside the education community, however, are only the tip of the iceberg. Biology books mention large numbers of terms in response to specifications that publishers get from the states. The specifications appear as lists or outlines that are formulated with vague goals or with state or national examinations in mind. Conversely, the examinations might be written with the textbook specifications in mind. Either way, the education community must bear a large measure of responsibility for the characteristics of textbooks.
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TEXTS, TESTS, AND CLASSROOM PRACTICE 31 Publishers are often required to produce a new book in only 6 months or so (Tyson-Bernstein, 19881. In part for this reason, they turn to groups of writers (commonly anonymous), who separately draft small sections of a book. For crafting a coherent textbook, this is a formula for almost sure disaster. Some of the most memorable textbooks (albeit not for high schools) were written by individual authors, for example, E. B. Wilson's Cell in Development and Inheritance (first publication in 1896), James Watson's Molecular Biology of the Gene (1965), and Linus Pauling's The Nature of the Chemical Bond (19391. Each of these authors had a single vision-perhaps idiosyncratic, but economical, unified, and clear. Writing textbooks is one of the most difficult challenges that scholars face, and even some of the most brilliant have failed. It is hard to see how the present manner of writing, often using panels of nonexperts pursuing questionable educational goals, can succeed. The current method of writing textbooks is illustrated in the preface to the teacher's edition of a widely used high-school biology textbook: The modern biology program was developed in conjunction with a thorough program of research and testing. The objective of this research and testing was to survey the wishes and concerns of American teachers of high school biology and to reflect those wishes arid concerns in the various components of this program. Of The publisher designed the text around "focus groups" that each consisted a moderator and about a dozen teachers from local high schools. The moderator showed the teachers various prototypes for the design of the table of contents, the writing style, and many other aspects of the book. The teachers responded, and representatives of [the publisher] noted the teachers' concerns and then modified the components accordingly. Note the casual use of teachers, the absence of input from practicing scientists, and the parody of research and testing. The next step is usually a national market survey. Because study (Weiss, 1987) has shown that 76% of classroom teachers are satisfied with the available books (a serious problem in itself), one is reminded of the commercials for beer in which it is revealed that those who drink a particular brand are found to prefer that brand. There is neither time nor incentive before full-scale production to field-test textbooks under conditions that might expose their weaknesses and lead to revision. (That constraint should be compared with the extensive testing of the biology texts first produced by the Biological Sciences Curriculum Study, BSCS, in the 1960s.) The number of illustrations, the use of color, and costs are increasing for both college and high-school texts (Blystone, 1989~. But to what purpose? Despite the emphasis on illustrations and their obvious technical quality, the pictures often fail to inform. A striking demonstration is the reproduction in
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32 FULFILLING THE PROMISE the Holt text (1989) of a 1961 Scientific American portrayal of the cell, which now appears in color and three dimensions, but with no change in substance. But during the intervening quarter-century, our understanding of cell structure changed dramatically in ways that are useful for understanding cell movement and cell differentiation. Illustrations like this therefore perpetuate incorrect or incomplete concepts. Illustrations often are not integrated with the text and are not easy to follow. Sometimes they are absurd, as when electron micrographs, which have no natural color, are shown in color. Many illustrations seem to come directly from the scientific literature and are too complicated for high-school students to understand. Does the publisher believe that they give a book an authority that would otherwise be absent? The main function of illustrations appears to be to impress prospective buyers, but in many new texts illustrations are often only decorative distractions. In summary, most biology textbooks are produced by publishers who are responding to educationally bankrupt market forces. They are written by authors who do not control the content of the books and who are not selected for their knowledge of biology. They are then edited to conform to grade- level readability scores and to accommodate local tastes and religious views. Whatever the educational merits of editing for grade-level readability, even the most casual reading of texts suggests that they are edited by people who know so little of the science that they introduce inaccuracy and confusion. Last, but not least, the current textbooks are not interesting; they fail to convey the fascination and wonder of living systems, thereby convincing many students that the study of biology is an onerous task. How Can Things Change? The problem of biology textbooks intersects with a number of other issues discussed in this report. If textbooks are to improve, there needs to be a greater emphasis on the place of concept and process in teaching biology and a clarification of the goals of science education in the sweep of years embraced by K-12. Achieving that emphasis will need consensus among teachers (as described in the section of the report on teacher preparation), changes in how we measure student accomplishment (as described in the section on testing), and changes in the expectations that state boards convey to publishers about texts. If those changes can be accomplished, publishers will find it in their interests to produce better texts. Improving textbooks is a national problem that requires national leadership. In Chapter 8, we propose the creation of a body that could address the problem of textbooks in ways set forth below.
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TEXTS, TESTS, AND CLASSROOM PRACTICE 33 Recommendations · A process of review of high-school texts that is open to the scrutiny of scientists should be instituted. Whatever their pedagogical merits, text- books need to be examined for scientific accuracy, interest, currency, and vision by scientists and outstanding teachers in a forum where the reviews will be widely available to teachers, members of school boards, and others at the grass-roots level. That is, the broader scientific community should be engaged nationally in collaboration with teachers in evaluating textbooks and locally in providing advice in textbook adoption. It is important that teams of reviewers include research scientists, teachers with experience in the school classroom, and individuals familiar with recent research on learning and on reading comprehension. A fuller examination of present texts for conceptual and factual errors would document further the need for change, enumerate principles that should be stressed in texts, and provide incentives to publishers to alter their mode of production. If conditions can be created in which reviews of books by scientists are truly influential in the processes of adoption, it will become not only possible but necessary for publishers to produce educationally worthy textbooks. · We need to explore ways in which first-class scientific minds can be engaged in the writing of high-school texts and the control of content can be shifted from publisher to author. We make this statement on the assumption that publishers will welcome serious discussion with scientists. We recognize that good books need not be written by individual authors; in fact, the team approach used by the BSCS, in which research scientists, science educators, and talented secondary-school teachers worked together, has a great deal to recommend it. What is essential is that the right people are involved and that enough time is devoted to the project to allow adequate classroom testing and analysis before books go to press. We could also see a fruitful collaboration develop between a foundation and a publisher for the development of a new text, but if such a project is launched, great effort should be made to see that the mistakes of the past are not repeated. · A new biology text should be much smaller than most of those now on the market. It should be designed around important biological concepts and principles and should cover fewer topics in greater depth. Moreover, it should be interesting to student and teacher alike. Technical language should be used sparingly and never as a substitute for lucid explanations of biological processes. In the design, writing, and editing of a book, the results of research on reading comprehension should be used fully. Illustrations not only should be accurate, but should be designed to promote understanding. Their conception must be part of the authors'
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34 FULFILLING THE PROMISE creativity, and they should not be left for editors and art departments to select. Illustrations that only decorate and distract do nothing to train the mind. · The committee has considered and rejected alternatives to text- books, such as booklets and videotapes. Although booklets could be topical, could be written by experts, and could be more readily revised than full- length texts, their disadvantages are considerable. The very perishability of loose-leaf or pamphlet formats would impose a cost that most school districts would find unacceptable. Resources that treat selected topics can be very effective in the hands of skilled teachers who are able to provide a conceptual framework to bind the course together, but we are skeptical that most teachers are ready to assume such responsibility for a course of the kind we believe should exist. Textbooks will continue, at least in the near term, to play a central role in most high-school classrooms in the United States. For videotapes and computer programs the considerations are sim- ilar. Although we favor the development of appropriate videotapes and software, we see these materials as playing only supplementary roles in the classroom. Books, however, represent a resource that students should learn to respect and use throughout their lives. In addition, the facilities for using videotapes and computer software are not universally available in American classrooms. Even if they were, there is little likelihood that videotapes and software of suitable quality and quantity could be produced in a short time. In the near term, however, videotapes and computer soft" ware could become very effective tools in teacher inservice programs, in addition to their supportive role in the classroom. This nation has a tendency to try quick technological fixes for national problems, but the solutions to our educational dilemma will not be found in that quarter. Good teachers are the key. We must look to teachers to provide instruction in science to our young people, and in this our teachers need enormous help and support. We must see that they are assisted by the best possible textbooks and not delude ourselves with the hope that merely putting teaching materials in new types of packages or on video screens will prepare our young citizens for the next century. LABORATORY ACTIVITY The Importance of Laboratory Activity Biology offers unique opportunities for students to observe and think about living organisms directly. Nevertheless, the study of life finds students mainly listening to lectures and reading most of each week, week after week (Stake and Easley, 1978; Mullis and Jenkins, 1988; Weiss, 1989~. Similar trends at
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TEXTS, TESTS, AND CLASSROOM PRACTICE 35 the undergraduate level are adversely affecting the preparation of new biology teachers (Merriam, 1988). The laboratory serves several crucial functions in the students' intellectual development. First, appropriately designed laboratory activities can challenge students' beliefs about the natural world and lead them to struggle with alter- native ideas until they can present scientific concepts accurately in their own words. The effectiveness of that mode of learning was implicit in some earlier approaches to the laboratory, was reinforced by the work of Piaget, and has more recently been broadly supported by findings in cognitive psychology (see, for example, West and Pines, 1985; Linn, 1986; Resnick, 1987~. Observation requires hypothesis and theory; without this framework, one does not know what to observe (Frank, 1957~. Exposing students' beliefs is important, for naive theories, once exposed, can be made explicit and then tested through further observation and experimentation. Second, laboratory investigations can enable students to generate knowl- edge directly from natural phenomena and learn how such knowledge can become reliable knowledge. It is in the laboratory that students can learn the power and characteristics of biology as an experimental science. Laboratory work and field work that are done effectively can enable students to understand scientific ways of knowing and the differences between those ways and other sources of knowledge. Third, direct hands-on experience produces lasting memory and, if properly reflected on, can lead to deep understanding of organisms and their environ- ments. Part of its benefit is motivation, because it is generally more interesting to study organisms directly than to read about them. Another benefit is en- gagement. Students can be involved in reading and listening, but participatory involvement with objects and events is more effective. Fourth, laboratory activity can help students to learn about precision and accuracy in observing, in record-keeping, in measuring, and in inferring. It can help students learn that the need for precision varies with human purpose. Fifth, laboratories and field studies can involve students in solving prob- lems: defining a problem and stating it as a hypothesis to be tested, determining what and how much evidence is required to make probable or to falsify the hypothesis, controlling variables, learning to use apparatus and techniques to gather valid information, assessing the sufficiency and validity of data gath- ered, making inferences and interpretations within the limitations of the data, and subjecting the interpretations to the criticism of peers and others (see, for example, the use of discretionary laboratories in Leonard et al., 19811. Finally, laboratory activities have the potential of introducing students to different technologies measuring instruments, laboratory apparatus, and electronic equipment and making them comfortable and skilled in using these tools in the quest for new knowledge. (Budgetary restraints will limit the degree to which this potential can be realized in high schools.)
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36 FULFILLING THE PROMISE In science, business, industry, and government, tools and technologies are integral to the workplace. Students must have experience with as many technologies as can be made available in the school setting and, even more important, be provided with opportunities to measure, observe, and infer in solving problems. In summary, laboratory activities can effectively help students to grapple with challenges to their beliefs about natural phenomena and to construct new conceptualizations (Novak, 1988~. To attain this overriding outcome, laboratory activities must have personal meaning for each student. As means to this end, laboratory activities should enable students to: · Formulate problems, devise methods for investigating problems, and solve problems individually or as team members or leaders. · Deliberate thoughtfully with peers and adults about the outcomes and meanings of investigations and reinvestigate to resolve conceptual contradic- tions. · Understand the limitations of small numbers of observations in gener- ating scientific knowledge. . Distinguish observation from inference, compare personal beliefs with scientific understanding, and comprehend the functions of hypothesis and theory in science and how theories are developed and tested. Select appropriate apparatus and use it with skill in conducting inves . tigations. · Develop familiarity with organisms and an interest in natural phenom- ena and acquire the knowledge and skills necessary to increase this interest. Current Failures of Laboratory Instruction The promise of laboratories has not been realized. The typical laboratory activity is a "cookbook" exercise that students can "do" with little intellectual engagement (Tobin, 1989~. Although laboratory work is second to lecture, accounting for about one-fifth of class time in tenth- to twelfth-grade sci- ence classrooms (Weiss, 1987 biology was not reported separately), it does not appear to contribute much to student understanding of biology, which is unimpressive (Mullis, 1989~. The use of laboratories in teaching biology is limited and has been de clining nationally for years (Stake and Easley, 1978; Mullis and Jenkins, 1988; Weiss, 19891. The decrease has occurred despite the major work done by the BSCS in developing investigative (as opposed to illustrative) laboratory activ- ities, both in the three versions of its biology texts and in its laboratory block and second-course programs (Mayer, 1978~. Several factors are contributing to the decline: the decrease in school resources for educational supplies and equipment; teachers' feeling that more time is needed to cover textbooks of increasing length; lack of adequate laboratory experience in teachers' prepa- ration, especially in college biology courses; length of the classroom period;
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TEXTS, TESTS, AND CLASSROOM PRACTICE 37 requirements that teachers move from room to room during the day; the time required for effective laboratory investigations; class sizes that are larger than laboratories and classrooms can accommodate; the lack of space in classrooms to facilitate extended laboratory investigations; inadequacy of funds for buses and substitute teachers for field trips; complaints of other teachers if students are away from their classes for field studies; and the logistics involved in having busy teachers, with too many students and different class preparations, care for and provide materials for classroom use (Stake and Easley, 1978; Hofstein and Lunetta, 1982; Tobin and Gallagher, 1987; Novak, 19881. Finally, laboratory work and field work reduce control of student behavior and can present disci- plinary problems, which might be especially difficult for inexperienced teachers or in situations where students do not find meaning in what they are doing. The goals of laboratory activity are not easily achieved, for without careful design and appropriate discussion of findings, students become confused and discouraged. For example, in a recent study of what constitutes successful lab- oratory work, Nachmias and Linn (1987) found that students accepted jagged graphs that described results obtained with insensitive instruments as reflecting the nature of cooling and heating. The explanation that the shape was caused by instrumentation failed to influence the students' explanations. Only when the phenomena were explored in depth with much discussion by students, with student-student and teacher-student questioning, and with explicit instruc- tion designed to help the students to link laboratory information and graphic representation with their knowledge of the natural world-did students develop "a fairly complex understanding of the interrelated factors that influence the smoothness of a heating or cooling curve" (Nachmias and Linn, 1987, p. 503~. Smith and Anderson (1984) came to similar conclusions in their study of experiments on respiration and photosynthesis. After traditional experiments with plants, students retained their naive concepts of food, respiration, and photosynthesis. Ten carefully structured laboratory experiments with extensive and carefully planned discussion and questioning of each experiment were required to achieve conceptual changes in which naive views of food were replaced with biological understanding. Conclusions Properly designed laboratory experiences are essential for effective high- school biology courses. The prevalent form of laboratory activities, which merely illustrate what the text has presented, do not produce the desired results and should be replaced with genuine investigations, designed and tested to enable students to achieve the conceptual changes necessary for intellectual development and understanding. Laboratory work and field work are therefore central to a major reconstruction of high-school biology education.
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42 FULFILLING THE PROMISE for words and definitions instead. Standardized questions that merely require simple recall or name association are of little value to either teachers or students. For example: The is the powerhouse of the cell. a) cell membrane by golgi apparatus c) mitochondrion d) nucleus A "correct" answer to this question in no way conveys an understanding of the important role the mitochondrion plays in cellular respiration. Standardized tests are generally norm-referenced, which means that they are developed to produce a distribution of scores, preferably a normal distri- bution. Questions that everyone answers correctly or that everyone misses are eliminated. Questions that are answered correctly by 30-70% of the examiners yield the best "reliability" scores. "Reliability" of a test is the degree to which the same score would presumably be obtained by a person if that person were tested again-it refers to the stability, dependability, and predictability of the test. Reliability is affected by the length of the test; in general, longer tests yield higher reliability. Because norm-referenced tests are designed to sort students on a normal distribution, the mean, median, and mode can shift if students do better or worse, but about half the students will always be "below average." Furthermore, research clearly shows the negative effects of normative grading on learning, motivation, and achievement (Eisenhardt, 1976; Robinson, 1979; Crooks, 1988~. There is something pernicious and destructive if pride of accomplishment must be tempered by the belief that one's performance is always "below average." The contents of standardized tests are developed from the major texts and curricular guides used throughout the United States and are presumably independent of the particular curriculum and instruction of any school or school system. Norm-referenced standardized tests offer efficiency in scoring, yielding numerical scores with high reliability; but they usually sacrifice validity (C. W. Anderson, 1989~. "Validity" refers to the degree to which a test measures what it was designed to measure for our purposes, understanding of science. Standardized tests rarely assess the application of knowledge, problem-solving, or the ability to think through issues that involve biological understanding. The tests, therefore, sort students, but on a scale that deflects judgments about the effectiveness of the curriculum. Students who score well on these tests might discover in college or elsewhere that they have been rewarded without real learning. An alternate to the norm-referenced test is the criterion-referenced test, which is used by many states to measure competence. Such tests consist of items related to specific objectives and generally incorporate, for a group
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TEXTS, TESTS, AND CLASSROOM PRACTICE 43 of items or the whole test, the criterion of acceptable success. Establishing the criterion of acceptability is essentially arbitrary for example, correctly responding to 70% of the questions. Test items like those administered by the NAEP are scaled to provide a criterion-referenced interpretation of levels on a continuum of proficiency (Mullis and Jenkins, 1988~. Selection of items for either type of test involves judgment, and it would be a mistake to assume that criterion-referenced tests address all the deficiencies of norm-referenced tests. Many items can measure the same concept and vary in difficulty. One cannot assume that test scores indicate accurately the degree to which a concept has been mastered, merely on the basis that the test was criterion-referenced, rather than norm-referenced (Klein and Kosecoff, 1973~. Teacher-Made Tests Tests can also be composed by individual teachers, and they might or might not include essay or other types of problems in addition to or in place of multiple-choice items. Such tests differ little from those given 30 or 40 years ago, except that fewer essay and more multiple-choice tests are used now. Examination of teacher-made tests indicates that, for the most part, they measure recall of isolated facts in a multiple-choice format (Robinson, 1989; Stiggins et al., undated). In design, tests made by teachers tend to follow the format of standardized tests. The Educational Impact of Tests The role of tests has been examined by many others. For example, in an extensive review, Crooks (1988) found that evaluation of students in the classroom appears to be "one of the most important forces influencing education." He found (p. 467) that classroom evaluation guides students' judgment "of what is important to learn, affects their motivation and self- perceptions of competence, structures their approaches to and timing of personal study (e.g., spaced practice), consolidates learning, and affects the development of enduring learning strategies and skills." A panel of the National Research Council (NRC) convened to review science tests concluded that the multiple use of single tests has led to the misuse of results (Murname and Raizen, 19881. Specifically, the panel recommends that: . Results from tests constructed for one purpose not be used for a quite different purpose. · School or classroom average test scores not be applied to individuals and individual test scores not interpreted as ratings or rankings of persons, but only of performance on a test that assesses specific skills.
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44 FULFILLING THE PROMISE . Test results or tests of the kind reviewed by the NRC panel not be used as the major force driving curriculum and instruction. Testing clearly plays important roles in education. Testing can help to motivate interest and generate enthusiasm for a subject, or it can smother interest and deaden curiosity. Testing can help to evaluate the success of programs, or it can drive a curriculum in the wrong direction. We are deeply concerned that the present system confuses the multiple roles of tests, to the detriment of education. With the recent press for accountability from national, state, and local agencies, testing programs are beginning to drive the curriculum. Teachers feel compelled to limit their efforts in the classroom to what and how school, district, or state tests assess. "Teaching to the test" is increasingly prevalent in high-school biology classrooms, as was vigorously expressed by many teachers in this committee's open forum during the November 1988 meeting of the National Association of Biology Teachers in Chicago. Dependence on norm- or criterion-referenced multiple-choice tests as they are currently constructed, either for grading students or for analyzing and creating educational policy, tends to misdirect students' habits of study. Rather than mastering concepts, students believe that recognizing terms in a multiple- choice format is the appropriate educational goal. This kind of testing has a major impact on how students go about studying and on the strategies they acquire for learning (Crooks, 1988~. In the long run, the impact of current modes of testing on enduring skills and strategies for learning will be inimical to reform. We cannot overemphasize the importance of this relationship. Resnick and Resnick (1985) make a strong argument for moving from standardized testing to a system of examinations designed to assess particular courses or curricula-examinations created for specific situations. Although in principle such test instruments could be norm- or criterion-referenced, a 1986 project of the NAEP (Blumberg et al., 1986) showed that ensuring that higher-order thinking skills (such as problem-solving) are assessed requires that students be interviewed by knowledgeable adults about responses to problems. Similar results were found in the United Kingdom after more than 7 years of work by the Assessment of Performance Unit (Driver et al., 1964~. (For an alternative view, see C. W. Anderson, 1989.) In the preceding section, we argued that laboratory work and field work are essential parts of an effective education in biology. However, there are few documented instances of the use of practical laboratory tests in biology (Robinson, 1979; Gallagher, 1986~. In light of traditional testing practices, it is not surprising that little is known about the effects of laboratory work on achievement in high-school biology. Tamir and Glassman (1970) found differ- ences between student scores on a 2-hour practical examination and teachers' grades; the practical examination seemed to be measuring something different
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TEXTS, TESTS, AND CLASSROOM PRACTICE 45 from what was covered in teachers' evaluations. Similarly, Robinson (1969) found a low correlation (r = 0.3) between a laboratory practical examination and a multiple-choice test on similar material. Failure to develop new test instruments to assess properly the outcomes-cognitive and affective, theoreti- cal and applied-of education in biology and especially of the contribution of laboratory work in biology in the current school and university climate could further reduce the commitment of staff and institutions to reform teaching and learning. Conclusions Citizens who lack knowledge and understanding are susceptible to those who confuse science and other ways of knowing, to the detriment of public understanding and rational decision-making. Understanding of central concepts and principles of biology will not be gained as long as classrooms and stan- dardized tests assess only recall and recognition. Tests that are consistent with a new commitment to understanding in depth are essential to enable teachers to know what they are accomplishing as they change their teaching methods and emphases. They are also necessary to inform students that different learning strategies are needed to achieve the goals of the biology course. The fundamental problem faced by evaluators is that they do not have adequate test instruments to determine whether students can use biological knowledge or whether some ways of teaching and learning are more productive than others. For the same reason, we also are not able to determine which major changes in teacher education would be most effective in changing students' achievements. Lack of instruments and methods that permit students to display what they have learned in a year of high-school biology limits the improvement of biology education. In addition, testing is increasingly driving curriculum and instruction in a dull and pedantic fashion, and that makes it imperative to address the issue of testing and evaluation in middle- and high-school biology at all levels national, state, school district, and classroom. If major changes are made in the curriculum, in instruction or teacher training or both, existing instruments will be too blunt to show differences in students' achievement in understanding, skills, or attitudes toward science. Continued use of the same kinds of assessment instruments and procedures that are now commonly used could lead to a worsening of the present situation, even in the name of reform. New outcomes and expectations could be nullified by outdated standards. A whole new array of test instruments and procedures should be developed to enable biology teachers to evaluate and improve their teaching and their students' learning. Means should be designed specifically to address how well schools are doing. Instruments should:
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46 FULFILLING THE PROMISE · Serve an educational function for students, helping them to understand their own progress and providing the necessary measurements required by others. Inform students of their ability to apply randomly selected biological principles and concepts to real problems personal, societal, and global. · Inform communities and the profession about the range of capabilities that students have developed in solving problems, as well as their attitudes toward biology and its relevance to their lives and their future. Require the use of scientific apparatus and procedures, such as labora- tory practical examinations. . Rev Hash. anal administrators in their critical inquiries into the quality of biology education by measuring the range of conceptual capabilities, attitudes, and skills exhibited by students. Such instruments and procedures should be sensitive enough to display dif- ferences in students' performance with changes in teaching and learning. If appropriately developed, such tests might drive the curriculum, but in ways that are in the best interests of students. Recommendations Several kinds of tasks need to be carried out by classroom teachers and school districts, states, and the nation. We do not need a national test, but rather tested models and problems that can be used for the assessment of biology education at district, state, or national levels. Testing research and technology have advanced to the point where they can make important contributions to biology education. The American College Testing Program (ACT) and the Educational Testing Service (ETS) seem to be developing new assessment methods, and the trend is encouraging. We have several specific recommendations, as outlined below: . A major effort is needed to develop, test, and publish model exam- inations, as well as sample questions and procedures to assess the desired outcomes of biology education-cognitive and affective changes and theoret- ical and applied knowledge. The examinations must be especially sensitive to the contribution of laboratory work in biology. They should use any technology that would enable measurement of the most essential outcomes of biology education as described throughout this document. Different tests should be designed for use at different levels-e.g., middle school and high school. They should serve more than traditional functions by involving students in thinking and reasoning (Haney, 1984~. Test-makers should consider the work of Blumberg et al. (1986), the Assessment Performance Unit in the United Kingdom (Driver et al., 1964), and other literature on
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TEXTS, TESTS, AND CLASSROOM PRACTICE 47 assessing performance (Stiggins, 1987; Eylon and Linn, 1988). In addition, continuing evaluation of the NABT/NSTA High School Biology Examination (a product of collaboration between NABT and NSTA) with a view to how these goals might be achieved is desirable. The utility and effectiveness of new tests should be examined by analyzing patterns of performance, rather than single numerical scores. A national group of biology teachers, biologists, teacher educators, and scholars in educational and cognitive psychology and measurement should be funded to collaborate in the development, testing, and implementation of new examinations. Teachers involved in the project should be released from some of their teaching responsibilities to permit direct involvement in this critical effort in instructional improvement. Once the materials are developed, pilot programs should be created for introducing preservice and inservice biology teachers to their appropriate use. A larger number of biology teachers and college professors who teach methods courses for biology teachers should be involved at this stage. After testing, the programs should be disseminated into many classrooms, with carefully designed research to demonstrate appropriate use and warn of problems that attend misuse of the materials and their adaptations. · A second initiative is needed to improve tests given regularly by biology teachers during the school year. Unless teachers are helped to construct measuring instruments that are consistent with the best practices and the agreed-on goals of biology education, their classroom tests will lead students to continue to cram for tests that require mere recognition of terms. This second project should follow the first when there has been enough time for the results of the first to be assessed. During development and field testing, the project should involve classroom teachers, university biologists, and persons knowledgeable about testing procedures. It should include the development of a series of problems designed to assess students' understanding of major biological concepts and ability to apply them. An appropriate outcome would be the creation of a package of widely avail- able training materials that might include a video tape or disk, computer software, and examples of how to analyze patterns of responses to related items. · The publishers of tests that accompany textbooks and other learn- ing materials need to improve the diversity and quality of their tests. Teachers have come to expect test booklets to accompany textbooks. Be- cause there is no market advantage to testing the quality of the tests, they do not constitute priority investments for publishers, and the schools' ready acceptance of them is a commentary on the low priority attached to testing. Efforts need to be pressed to enlist the cooperation of university biologists, teachers, science educators, and publishers in improving, through
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48 FULFILLING THE PROMISE field testing, the assessment materials that accompany textbooks. Informa- tion on testing conditions, instructional goals, relation to the text materials, and ranges of student performance should be published in standard reports that accompany textbooks. Unfortunately, given the markets in which pub- lishers swim or sink, we cannot be sanguine about the likelihood that they will meet this challenge until the expectations and practices of teachers and schools are substantially altered. · States and school districts should move swiftly to recognize the need for new tests. Low-quality tests or tests that are not based on appropriate educational goals should not be accepted from publishers. States and school districts should avoid using results of paper-and-pencil tests as the sole criterion of the effectiveness of their biology programs. Tests that are developed locally should go through a careful process to ensure their validity for assessing the outcomes of biology education with respect to essential goals. Several indicators (measures that allow a judgment to be made as to whether a given condition is getting better or worse), as described by Murname and Raizen (1988), should be included with test results when the results are reported. It is essential that indicators be related to student understanding, be operationally defined, and be kept with test results year after year. The processes of evaluation cannot be addressed in isolation from what is in textbooks, how teachers are taught, the conditions under which teachers work, and public consensus about the goals of science education. Moreover, as science changes, educational goals must be tuned. Biology is a rapidly changing field of study, posing conceptual shifts and generating new social and ethical issues. The issues raised by testing and evaluation cannot be solved without persistent, continuous attention by a broad spectrum of experts. In addition to the interdependence of testing, textbooks, preservice pro- grams, and inservice programs, there is a second compelling reason to look at testing with a fresh eye: the purposes of norm-referenced testing do not serve the goal of improving teaching and learning. We need a national perspective concerned more with evaluating the effects of curricula, teaching methods, and materials than with ranking the performance of individual students. We need to develop ways to probe the system's components, rather than the relative ranks of the learners. Existing institutions with a role in testing are not designed to pursue that objective by themselves. In Chapter 8, we propose a formula that is free of constraint from govern- ment, business, or any other constituency, but calls on the scientific-research and educational-research communities for valid judgments that will be helpful to biology teachers, parents, administrators, school boards, and state departments of education.
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TEXTS, TESTS, AND CLASSROOM PRACTICE OTHER FACTORS THAT HINDER EFFECTIVE EDUCATION 49 Effective teaching of biology or any other subject requires a broad and deep knowledge of the material to be taught, instructional skills, a willingness to give of oneself to others, and a commitment that continues after the last child leaves the classroom for the day. In short, teaching is a profession. Among the problems that beset teaching, however, are the nonprofessional burdens that teachers in many schools must bear. Most of those burdens reflect ills in the larger society, but they are often manifested in the classroom, where teachers are not prepared to deal with them. Pernicious problems-such as the sale and use of illegal drugs and the violence that accompanies them, pregnancy of teenagers, and high dropout rates are becoming endemic in the nation's public schools. The professionalism of teachers is further vitiated when, in addition to responding to continual crises in the classroom, they are expected to respond to political pressures for accountability and cost-effectiveness. With the increasing public clamor for educational reform, what passes for leadership has all too often fallen solely to politicians, and authority is increasingly centralized in district and state offices of education. That trend has furthered the loss of professionalism among teachers, as decisions about textbooks and objectives have been removed from their control and pressures to teach to examinations have increased. But results of research indicate that the combination of autonomy of schools and teachers with parent participation is the key to high academic achievement (Chubb, 1988), a standard indicator of successful teaching. A great disparity exists between the goals of teaching and the possibility of reaching those goals in the present teaching environment. The reality of the teaching environment does not bode well for the current wave of educational reform. Within schools, for example, state or local policies often impede effective science teaching. If classrooms have 30 pupils, teachers might have to relate to 150 different children each day. Many classrooms must be shared by teachers, and a teacher must go elsewhere for some periods. Typically, periods are a rigid 45 minutes long, and there is no opportunity during the working day to set up a classroom for laboratory activities. Laboratory facilities, if they exist, are underfunded. Under those circumstances, it is nearly impossible to teach science to students in a manner that is not built around workbooks, lectures, and memorizing. The absence of time for anything but the minimum makes creative teaching difficult. There is no time to prepare or to reflect and no released time to attend workshops and conferences, to visit other classrooms, or to work with colleagues (even in the same school), to set common curricular goals, to plan together, or to discuss and plan examinations (Taylor, 19891. Teachers are assigned to monitoring hallways between classes or dispensing drinking straws in the cafeteria activities that can only leave them wondering why they were ever
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50 FULFILLING THE PROMISE attracted to the profession of teaching. Although decision-makers are generally aware of the extent to which working conditions undermine the professional nature of teaching, they are often unable to change the policies. These policies also convey a lack of understanding of the special role that science plays in a student's education at all levels, as well as the special conditions needed for successful instruction in science. In addition to the nonprofessional burdens endured by teachers, other aspects of the teaching environment impede effective education. The classroom has become a microcosm of the myriad social and economic problems of society. Teaching toward the goal of academic excellence is but one of the many tasks that teachers are expected to perform. Schools are expected to serve other purposes, such as socializing young people into their culture and preparing students for specific occupations. But life experiences that students bring into the classroom affect how receptive they are to learning. Teachers are expected to help students overcome their nonschool problems. An endemic culture of poverty in the inner cities of large urban centers perpetuates harmful social activities. Moreover, peer pressure often discourages students from even trying to succeed academically (Chubb, 1988~. A recent report of the Institute of Medicine brought to light the prevalence of mental illness among our nation's youth (Institute of Medicine, 19891. Inadequate pay provides little incentive for teachers to stay in the teaching profession in the face of these and other obstacles, such as overwork and the violence directed at teachers and students in large urban areas. Teachers must also overcome the negative image of science held by students and often by their parents. Overcoming the barriers to effective education is often left to the teachers, who are helpless to effect any major change, given the dynamics of a system over which they have little control. Instead, they are forced to work within a hierarchical system imposed by both school systems and teachers' unions. One example involving salary will illustrate the point. Except for states with a single, statewide salary schedule, each school district sets remuneration with the usual provision that teachers will not be hired into the district at a salary that recognizes more than 6 years of experience. Therefore, senior teachers who leave a school district must take salary cuts to move. In effect, unlike members of most university and business professions, public-school teachers who have stayed in a school district (or state) for more than several years become permanently indentured servants. The members of no other profession are so hobbled. If the goal of effective education is to be realized, teachers must be given more control over the system in which they work.
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TEXTS, TESTS, AND CLASSROOM PRACTICE 51 Recommendations The following recommendations will expedite reform by increasing the professionalism of teaching. · Seriously addressing the need to teach science more effectively will require changing some current administrative practices. More flexibility is required in the scheduling of classroom and preparation time, in the pursuit of related professional activities by teachers, and in teachers' sharing of responsibilities. This recommendation carries some inevitable fiscal implications, and a word on that score is appropriate. Goals of "reform" are of two kinds. The first merely specifies minimal accomplishments that can be effected by policy changes or new rules. The second aims higher by attempting to alter the result of the educational process in some fundamental way, e.g., by maximizing the intellectual accomplishments of individual pupils. Requiring more courses for graduation, lengthening the schoolday, and inserting yet another normalized test are examples of the first. Although they might seem to speak to the problem, by themselves they are merely political palliatives that leave the impression that something important is being done. In contrast, changing the outcome of schooling in a basic way seriously disturbs the system and presents a challenge to virtually every interest group on the scene teachers, administrators, and taxpayers (Airasian, 1989~. True educational reform will be expensive and rock many boats, and those who must pay for change should be clear about the goals they wish to achieve. · Obstacles to effective teaching must be lifted. Inasmuch as text- books and testing play major roles in determining how biology is taught, teachers must be encouraged to experiment with new techniques of peda- gogy and assessment. School policies, rather than perpetuating isolation, should be tailored to support and encourage teachers in working together in developing ideas. School administrators can endorse activities for teachers to share ideas about new curricular approaches through policies allowing released time and "free" time during the school day. Teachers must also be encouraged to exchange information about what works and what does not work in the classroom-e.g., pedagogical techniques and laboratory ap- proaches. School policies should encourage teachers to become involved in new curricular projects and should assure them of long-term commitment and support for successful innovative efforts. · The nonteaching tasks assigned to teachers should decrease. Teach- ers should be expected to devote nonteaching time to activities that will enhance their ability to teach, such as laboratory preparation and tutoring students. Valuable time should not be spent in monitoring hallways or supervising lunchrooms.
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52 FULFILLING THE PROMISE · School boards must be convinced that hiring experienced teachers, who are paid more than less-experienced teachers, is sometimes best for the children in the district. Market forces would then play a greater role in public-school education. Districts that provided the best working conditions for effective teaching would be able to attract the best teachers. Other districts might have to improve working conditions and salaries, if they are to retain or attract highly qualified teachers. Through such a change in the conditions of teacher employment, both teachers and school boards would have freer hands in creating faculties and working conditions that lead to schools that communities would wish to support with enthusiasm.
Representative terms from entire chapter: