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National Research Council (US) Committee on High-School Biology Education; Rosen WG, editor. High-School Biology Today and Tomorrow: Papers Presented at a Conference. Washington (DC): National Academies Press (US); 1989.

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High-School Biology Today and Tomorrow: Papers Presented at a Conference.

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19Teaching High-School Biology: Materials and Strategies

Rodger W. Bybee

Whom Are We Teaching Biology?

High-school biology is offered in 99% of high schools in the United States (Weiss, 1987). This is a 4% increase since 1977 (Weiss, 1978). Biology is the most commonly offered science course—35% of all science courses. Half of all science classes relate to the biological sciences (Weiss, 1987). It is safe to say that biology is taken by the majority of high-school students. And for many of those students, biology is the last science course they will take.

It is absolutely essential to consider the demographics of education as we look for a reform of biology education. In All One System, Harold Hodgkinson (1985) presents demographic trends—changes in population groupings that move through the educational system. Hodgkinson summarized his findings (p. 7):

What is coming toward the educational system is a group of children who will be poorer, more ethnically and linguistically diverse, and who will have more handicaps that will affect their learning. Most important, by around the year 2000, America will be a nation in which one of every three of us will be non-white. And minorities will cover a broader socioeconomic range than ever before, making simplistic treatment of their needles. even less useful.

Other national reports serve to remind us that our educational programs at the precollege level must recognize the personal needs of all youth and the aspirations of society. One such report is The Forgotten Half: Non-College Youth in America (Commission on Work, Family, and Citizenship, 1988). This report is a counterpoint to the numerous reports that explicitly or implicitly focus on the college-bound student.

Whom are we teaching biology? We are teaching the majority of students. And we must recognize that the majority is a diverse group, with different needs, perceptions, and aspirations. High-school biology should be designed for all students, those who are college-bound and those who will enter the workforce immediately after high school.

Characteristics of Students

Contemporary research findings about students as learners underlie my discussion of instruction. One finding is that students are motivated to learn science. They are naturally curious about all aspects of the biological world. Whether it is recognizing plants and animals, understanding biotechnology, or investigating ecological systems, students have an interest in their world and seek explanations for how things work.

A second finding is that students already have explanations, attitudes, and skills when a biology lesson begins. Students' explanations, attitudes, and skills may well be inadequate, incomplete, or inappropriate. Contemporary educational researchers use such terms as ''misconceptions" and "naive theories" to characterize the cognitive component of student understanding. Briefly, students interpret instructional activities in terms of what they already know; then they actively seek to relate new concepts, attitudes, or skills to their prior set of concepts, attitudes, or skills. The assimilation of new experiences is based on the students' prior experiences, and it may or may not get "learned" the way the teacher intended. Students' learning is accurately viewed as the process of refining and reconstructing extant knowledge, attitudes, and skills, rather than the steady accumulation of new knowledge, attitudes, and skills.

A third finding is that students have different styles of learning. "Learning style" refers to the way individuals perceive, interact with, and respond to the learning environment. Learning styles have cognitive, affective, and physical components. While instructional strategies vary between and within projects, they are based on the idea that learning style is an aspect of students' learning and should be recognized in the strategies of teaching.

The fourth finding is that students pass through developmental stages and that tasks influence learning. In the 1960s and 1970s, Jean Piaget's theory was popular, and it influenced curriculum development. Piaget's work concentrated on cognitive development. Current research in the cognitive sciences is, in many respects, an extension of Piaget's theories. Contemporary curriculum development holds a larger view of student development. In addition to cognitive development, we should also attend to the student's ethical, social, and psychomotor development. This broader view of development is important to the selection of instructional methods.

The general view of student learning presented in the four findings is constructivist. In the constructivist model, students reorganize and reconstruct core concepts, or intellectual structures, through continuous interactions with their environment and other people. Applying the constructivist approach to teaching requires the teacher to recognize that students have conceptions of the natural world. Those may be inadequate and need further development. Curriculum developers can design materials and teachers can use strategies so that students encounter objects or events that focus on the concepts, attitudes, or skills that are the intended learning outcomes. Then they can have students encounter problematic situations that are slightly beyond their current level of understanding or skill. The instructional approach then structures physical and psychological experiences that assist in the construction of more adequate explanations, attitudes, and skills. These new constructions are then applied to different situations and tested against other constructions used to explain and manipulate objects and events in the students' world. Briefly, the students' construction of knowledge can be assisted by using sequences of lessons designed to challenge current conceptions and by providing time and opportunities for reconstruction to occur.

What Should We Teach?

Through most of time, the immense journey of biological evolution has been directed by natural laws. With scientific and technological advances, such as the discovery of DNA and the development of biotechnology, and with the problems of population, resources, and environments—such as famine, destruction of tropical rain forests, and ozone depletion in the upper atmosphere—we have abilities and influences that go beyond our meager understanding and myopic visions. Evolution may now be directed by humans themselves. Here is a clear and profound connection between biology as a pure science and the influence of biology on our global society. Students need an ecological perspective. All other arguments for a particular curriculum emphasis in biology pale in comparison.

A recent editorial in Science (Koshland, 1988) descried the importance of ecological understanding:

Ecology, the study of the delicate balance between species and environment ... shows that evolution has developed clever strategies ... to use resources to maximum effectiveness. Those strategies sometimes involve symbiosis, sometimes tacit agreements on territory, and sometimes murderous aggression, but all are based on the assumption that resources are limited so that the clever and the parsimonious will gain relative to the inefficient and wasteful.

At the end of the editorial, Koshland made a clear connection to human populations:

Most species struggle to overcome poverty of resources and occupy niches that allow a critical number to survive in competition with other species. Modern civilization has upset that process so that many (although certainly not all) humans are living far beyond a survival level. The brain that allowed that situation needs now to curb a primordial instinct to increased replication of our own species at the expense of others because the global ecology is threatened. So, ask not whether the bell tolls for the owl or the whale or the rhinoceros; it tolls for us.

This powerful statement has the implied theme of educating the public about global ecology. The public has an increased awareness and concern related to interactions among individuals, groups of individuals, and the environment. Public attention is directed to these primary units of ecological study. This attention has influenced the growing public concern for ecology and public debate about policies that extend the concern to human ecology.

In biology education, there has been an essential tension between the need to teach "real biology"—the science of life—and the need to achieve educational goals related to personal development and societal aspirations—the science of living. The continuing debate about the primary goals—whether the biology curriculum ought to be a science of life or a science of living—is essential to the continued evolution of biology education. The history of this debate has been described elsewhere (Rosenthal and Bybee, 1987, 1988). I perceive the contemporary resolution of the debate to favor human ecology, which should be the conceptual framework for the curriculum in biology.

The teaching of human ecology is an integrative endeavor among humanists, social scientists, and natural scientists. Separate disciplines—such as biology, sociology, psychology, anthropology, economics, philosophy, theology, and history—evolved to improve understanding of the human condition and, we may assume, the human predicament. Now, when problems cut across these disciplines, there is reluctance to transcend the disciplinary boundaries. Such reluctance must be overcome for the very reasons for which disciplines were invented—the cause of human understanding, if not survival. The idea of cooperation among the various disciplines serves to maintain the integrity of disciplines while permitting study of the unifying conceptual schemes of biology and the central issues of human ecology—population dynamics, growth, resource use, environmental practices, and the complex interaction of human populations, resources, and environment (Moore, 1985; Ehrlich, 1985).

Textbooks

To say that generally the biology textbook is the organizing framework for the curriculum and reading the textbook is the dominant method of instruction is not an overstatement. Over 90% of science teachers use published textbooks (Weiss, 1978, 1987). And science instruction tends to be dominated by teacher lectures and reading of the textbook (Weiss, 1987; Mullis and Jenkins, 1988). Any consideration of reforming high-school biology must examine the role of the textbook in instruction.

There is a contradiction associated with the use and review of textbooks. A majority (76%) of science teachers in grades 10-12 do not consider textbook quality to be a significant problem (Weiss, 1987). On the other hand, many educators do consider textbook quality and usability to be problems (Muther, 1987; Carter, 1987; AAAS, 1985; Apple, 1985; Armbruster, 1985; Moyer and Mayer, 1985; McInerney, 1986; Rosenthal, 1984).

Science teachers are clearly satisfied with the quality of textbooks. In a national survey of science education, Weiss (1987) asked several specific questions about the quality of science textbooks. Some of the items that received favorable ratings by a majority of respondents are the following:

  • Have appropriate reading level (87%).
  • Are interesting to students (52%).
  • Are clear and well organized (85%).
  • Develop problem-solving skills (61%).
  • Explain concepts clearly (74%).
  • Have good suggestions for activities and assignments (74%).

Why are the teachers satisfied? The textbooks are meeting teachers' needs and their conceptions of good biology and appropriate biology education. The problem here is similar to that of the biology student who has misconceptions about the energetics of cells or the mechanisms of evolution. The means of changing the misconceptions is likewise similar. There is need to challenge current concepts and introduce biology teachers to perceptions about textbooks that are counter to their own. Then, provide time, opportunities, and examples that allow teachers to reform their ideas.

We may also have to consider the questions that probe beyond those asked in the survey. For instance, the material is clear and well organized; but should we be teaching that material? Or, the textbooks develop problem-solving skills; but which problem-solving skills, and are they really developed? The problem of teacher satisfaction with textbooks is central to any reform of biology education.

Content and pedagogy are central to the textbook situation. One assessment of content is the copyright date of textbooks in use. Seventy-one percent of science classes in grades 10-12 use books with a copyright date before 1983, and 22% before 1980. So one dimension of the content problem is that the information is dated.

Gould (1988) published "The Case of the Creeping Fox Terrier Clone," in which two themes were developed. One was the presentation of controversial issues, such as evolution, in textbooks. The second, and more important, was that textbooks in a given market, like tenth-grade biology, are very similar to one another. Gould did an informal review of biology textbooks and had this to say (1988, p. 19):

In book after book, the evolution section is virtually cloned. Almost all authors treat the same topics, usually in the same sequence, and often with illustrations changed only enough to avoid suits for plagiarism. Obviously, authors of textbooks are copying material on a massive scale and passing along to students will considered and virtually xeroxed versions with a rationale lost in the mists of time.

At the end of the article, Gould remarked on the educational effect of cloning (p. 24):

[Textbook cloning] is the easy way out, a substitute for thinking and striving to improve. Somehow, I must believe—for it is essential to my notion of scholarship—that good teaching requires fresh thought and genuine excitement and that rote copying can only indicate boredom and slipshod practice. A carelessly cloned work will not excite students, however pretty the pictures. As an antidote, we need only the most basic virtue of integrity—not only the usual, figurative meaning of honorable practice but the less familiar, literal definition of wholeness. We will not have great texts if authors cannot shape content but must serve a commercial master as one cog in an ultimately powerless consortium with other packagers.

What about pedagogy? The design of textbooks supports the science teachers' increased use of lecture and decreased use of laboratory (Weiss, 1987). One can imagine the situation getting worse, because the feedback within the system will continue to support the trend. More information is added to textbooks, but teachers have a fixed time to cover information. Fewer laboratory experiments are done, because more time is needed for lectures. Somehow, the cycle must be interrupted.

Reforming the content and pedagogy of textbooks is a complicated and complex proposition. Who is in control? Authors? Publishers? State adoption committees? Curriculum developers? Administrators? Teachers? The fact is that all groups are in some control and to some degree controlled. Most of the feedback in the system tends to perpetuate the current situation. It will take the concerted efforts of those within the system to bring about change. How might this happen? We need only look back 30 years to find a historical example. Support for several innovative biology programs, such as those developed in the late 1950s and 1960s, could bring about some change. Those programs incorporated the best scientists and teachers in the design of new textbooks. The original development and field-testing of materials was heavily supported and unencumbered by restraints of the market, adoption committees, and administrative budgets. The science-education community united to develop innovative programs; then the market adapted.

What should we do differently in the 1980s? First, I think several different groups should be developing biology programs. While the Biological Sciences Curriculum Study (BUSCH) was successful in developing three programs, I think there is need for even more diversity. Second, the projects should be funded by both private and public sources. The reasons for this are to encourage greater diversity and innovation of programs and to provide enough funding for significant innovation, such as the integration of technology (educational software), and major field-testing of the programs. Third, only publishers that are willing to give control of content and pedagogy to the developers should be involved in the projects, and those publishers should be involved throughout the development process. Fourth, development should include implementation of the program. Finally, teacher education at the preservice level should be integral to development and implementation of the new programs.

Technology

The use of educational technology has great potential for improving instruction in biology. According to Weiss (1978), computer use increases with grade levels, with approximately 36% of science classes in grades 10-12 using computers. Although the amount of time computers are used is small, at grades 10-12 computers are used primarily for drill and practice, for simulations, for learning content, and as laboratory tools (Weiss, 1987). In contrast to 1977, the 1985-1986 national survey indicated that computers are a part of science education. I assume that the trend toward increased use of computers will continue. Among the justifications for greater use of computers are the demands of an increasingly information-oriented and technological society and use of computers in the workplace (Ellis, 1984).

There have not been sufficient quantities of good software and affordable hardware for computers to have a widespread impact on curriculum and instruction in biology. Individual pieces of software are used as supplements to instruction. But the occasional application of a tutorial or simulation is not enough to bring about the reformation of thinking required to incorporate computer technologies fully into the biology program. As hardware and software evolve, there is reason to believe that they will become integral components of biology education (R. Tinker, unpublished manuscript).

There are three types of software that have immediate and important implications for instruction in biology: HyperCard, microcomputer-based laboratories, and modeling.

HyperCard

Textbooks have reached the point of diminishing returns relative to the amount of information they can reasonably contain for high-school biology. HyperCard is an educational technology that has relevance for the problem of teaching students how to ask questions and get information on selected subjects. They can simply view the information that someone else has organized, or they can "collect" information and organize it in a notebook (Kaehler, 1988).

Biology teachers are concerned that students must "learn" information that teachers do not have time to teach. HyperCard allows the students to gain access to information when they need it, to the depth that they want.

Microcomputer-Based Laboratory (MBL)

MBLs permit the acquisition of data in the laboratory through probes and sensors linked with a computer. This educational application was pioneered by Robert Tinker at Technical Education Research Centers. Data types that might be used in biology instruction include temperature, sound, light, pressure, distance measurement, electrical measurements (such as resistance and voltage), and physiological measurements (such as heart rate, blood pressure, and electrodermal activity).

MBL offers extensions of many current laboratories in biology education. It has several educational advantages, such as immediate feedback for students, capability for long-term collection of data, and easy construction of graphs for display of data. There is little reason not to use this technology in biology instruction.

Models and Simulations

Modeling tools are available in software packages that assist students in quantitative assessment. STELLA is the archetype of this software (Tinker, unpublished manuscript). Modeling applies very nicely to such subjects as population growth, resource depletion, and environmental degradation. Simulations provide students with opportunities to try ideas, change variables, and run hypothetical experiments. Computer technology affords the opportunity for students to investigate topics that they ordinarily could not study.

Teaching

My discussion of teaching is divided into two sections. The first concerns the laboratory and the second argues for a more systematic approach to instruction. The 1985-1986 national survey indicated that since 1977, science teachers have increased the amount of time in lecture and decreased the time in laboratory activities (Weiss, 1987). There is a need to renew and expand the emphasis on the laboratory and inquiry strategies (Costenson and Lawson, 1987).

Human Ecology and the Biology Laboratory

Human ecology is the conceptual orientation that I recommend for the biology laboratory (Bybee, 1984, 1987). Human ecology as a specific approach to the laboratory is described in Bybee et al. (1981). The following are characteristics of a laboratory program with a human ecological approach. The characteristics describe an orientation and direction for the science laboratory. Table 1 compares traditional and human ecological approaches to the science laboratory.

Table 1. Comparison of Traditional and Human Ecological Approaches to Science Laboratory.

Table 1

Comparison of Traditional and Human Ecological Approaches to Science Laboratory.

Study of Significant Problems

Laboratory activities will be related to problems in the human environment. Problems arise from situations that involve a question, discrepancy, or decision concerning the student, society, or the environment. Investigations should be selected that provide opportunities for students to help to define problems significant to them—problems that they think they can and are willing to help to solve (Bybee et al., 1980). Investigations should be oriented toward ways of acquiring information and using that information in making decisions about current personal and social problems. The following subjects could form the basis for study: world hunger and food resources, population growth, air quality and atmosphere, water resources, war technology, human health and disease, energy shortages, land use, hazardous substances, nuclear reactors, extinction of plants and animals, and mineral resources. The selection of subjects is based on surveys of different populations, including American citizens (Bybee, 1984) and science educators in other countries (Bybee, 1987).

Study of Ecosystems

An instructional orientation toward the ecosystem is appropriate. Of necessity, biology teachers will have to include other levels of biological organization, but students can experience and understand many changes in ecosystems, especially as they study them at local levels.

An ecosystems perspective is a good way to integrate various disciplines; it provides a common conceptual framework and language. The perspective could be introduced early in the biology program and thus provide concepts and terminology for the students' continuing study.

Holistic Methods of Study

Ecologists use holistic perspectives in scientific inquiry. Holistic methods can develop the students' ability to identify various interacting parts of systems (subsystems) and to understand the behavior of whole systems. Holistic methods of study are complementary to reductionistic methods, and students should experience the appropriate application and unique strengths of these methods.

Integrative Study

Biology education has held as important goals the development of and the ability to use biological concepts and methods of biological investigation. An orientation toward human ecology expands these goals in an effort to understand and resolve human problems. Human ecology provides experience in decision-making as a means to help students contribute to the eventual amelioration of problems. Decision-making implies some understanding of the social, political, and economic realms, as well as ethics and values. The primary emphasis of biology education programs should be on the concepts and processes of biology and biological investigation. A secondary emphasis is on the application of other disciplines in the cause of understanding and resolving problems.

Development and Learning

Instruction reflecting a human ecological approach should reflect an understanding of students as learners. Obviously, a global perspective of problems related to such issues as population growth or food resources is beyond the grasp of younger children. But local problems and some basic concepts—such as the difference between arithmetic growth and exponential growth—are not too complex for young children. Successful laboratory instruction in human ecology requires recognition of students' cognitive development and learning limitations.

Perspectives of Space, Time, and Causal Relations

Laboratory experiences should expand students' perspectives of space, time, and causal relations. Over the school years, students should extend their ideas of space from local to regional to national to global perspectives. Their ideas of time should extend to the distant past and to the future. Causal relations should extend from simple cause and effect to the complexities of interrelated and interdependent systems with multiple causal relations. In the end, we are trying to develop students with a global perspective who recognize complex interdependences and consider the future of humanity

It is time to place the laboratory back in biology instruction. The justifications for laboratory experience far outweigh the excuses for lecture and discussion (Costenson and Lawson, 1987; Mullis and Jenkins, 1988).

An Instructional Model

One of the major problems in biology education is the need for instruction that integrates textbooks, technology, and laboratory experiences. The instructional model proposed here is based on a constructivist approach and has five phases: engagement, exploration, explanation, elaboration, and evaluation. The model includes structural elements in common with

the original learning cycle used in the Science Curriculum Improvement Study (SCIS) program (Atkin and Karplus, 1962) and later discussions and research on the SCIS model (Renner, 1986; Lawson, 1988).

The five phases may be summarized as follows:

Engagement

This phase of the model initiates the learning task. The activity should (1) make connections between past and present learning experiences and (2) anticipate activities and focus students' thinking on the learning outcomes of current activities. The student should become mentally engaged in the concept, process, or skill to be explored.

Exploration

This phase of the model provides students with a common base of experience within which they identify and develop current concepts, processes, and skills. During this phase, students actively explore theft environment or manipulate materials.

Explanation

This phase of the model focuses students' attention on a particular aspect of theft engagement and exploration experiences and provides opportunities for them to verbalize their conceptual understanding or demonstrate theft skills or behaviors. This phase also provides opportunities for teachers to introduce a formal label or definition for a concept, process, skill, or behavior.

Elaboration

This phase of the model challenges and extends students' conceptual understanding and allows further opportunity for students to practice desired skills and behaviors. Through new experiences, the students develop deeper and broader understanding, more information, and adequate skills.

Evaluation

This phase of the model encourages students to assess theft understanding and abilities and provides opportunities for teachers to evaluate student progress toward achieving the educational objectives.

References

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  • Bybee, R. 1984. Human ecology: A perspective for biology education. Monograph Series II. Reston, Va.: National Association of Biology Teachers.
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Footnotes

Rodger W. Bybee is associate director of the Biological Sciences Curriculum Study (BSCS) in Colorado Springs. Before joining BSCS, Dr. Bybee was associate professor Of education at Carleton College. He is principal investigator for the new BSCS elementary-school program, Science for Life and Living: Integrating Science, Technology, and Health.

Copyright © 1989 by the National Academy of Sciences.
Bookshelf ID: NBK218805

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