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Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.

Appendix C
Three Statements in Support of Teaching Evolution from Science and Science Education Organizations

1. A NSTA (National Science Teachers Association) Position Statement on the Teaching of Evolution3

Approved by the NSTA Board of Directors, July 1997

Introductory Remarks

The National Science Teachers Association supports the position that evolution is a major unifying concept of science and should be included as part of K—College science frameworks and curricula. NSTA recognizes that evolution has not been emphasized in science curricula in a manner commensurate to its importance because of official policies, intimidation of science teachers, the general public's misunderstanding of evolutionary theory, and a century of controversy.

Furthermore, teachers are being pressured to introduce creationism, creation "science," and other nonscientific views, which are intended to weaken or eliminate the teaching of evolution.

Within This Context, NSTA Recommends that:

  • Science curricula and teachers should emphasize evolution in a manner commensurate with its importance as a unifying concept in science and its overall explanatory power.

  • Policy-makers and administrators should not mandate policies requiring the teaching of creation science or related concepts such as so-called "intelligent design," "abrupt appearance," and "arguments against evolution."

  • Science teachers should not advocate any religious view about creation, nor advocate the converse: that there is no possibility of supernatural influence in bringing about the universe as we know it. Teachers should be nonjudgmental about the personal beliefs of students.

  • Administrators should provide support to teachers as they design and implement curricula that emphasize evolution. This should include inservice education to assist teachers to teach evolution in a comprehensive and professional manner. Administrators also should support teachers against pressure to promote nonscientific views or to diminish or eliminate the study of evolution.

  • Parental and community involvement in establishing the goals of science education and the curriculum development process should be encouraged and nurtured in our democratic society. However, the professional responsibility of science teachers and curriculum specialists to provide students with quality science education should not be bound by censorship, pseudo-science, inconsistencies, faulty scholarship, or unconstitutional mandates.

  • Science text books shall emphasize evolution as a unifying concept. Publishers should not be required or volunteer to include disclaimers in textbooks concerning the nature and study of evolution.  

NSTA Offers the Following Background Information: The Nature of Science and Scientific Theories

Science is a method of explaining the natural world. It assumes the universe operates according to regularities and that through systematic investigation we can understand these regularities. The methodology of science emphasizes the logical testing of alternate explanations of natural phenomena against empirical data. Because science is limited to explaining the natural world by means of natural processes, it cannot use supernatural causation in its explanations. Similarly, science is precluded from making statements about supernatural forces because these are outside its provenance. Science has increased our knowledge because of this insistence on the search for natural causes.

The most important scientific explanations are called "theories." In ordinary speech, "theory" is often

Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.

used to mean "guess," or "hunch," whereas in scientific terminology, a theory is a set of universal statements which explain the natural world. Theories are powerful tools. Scientists seek to develop theories that

  • are internally consistent and compatible with the evidence

  • are firmly grounded in and based upon evidence

  • have been tested against a diverse range of phenomena

  • possess broad and demonstrable effectiveness in problem solving

  • explain a wide variety of phenomena.  

The body of scientific knowledge changes as new observations and discoveries are made. Theories and other explanations change. New theories emerge and other theories are modified or discarded. Throughout this process, theories are formulated and tested on the basis of evidence, internal consistency, and their explanatory power.

Evolution as a Unifying Concept

Evolution in the broadest sense can be defined as the idea that the universe has a history: that change through time has taken place. If we look today at the galaxies, stars, the planet earth, and the life on planet earth, we see that things today are different from what they were in the past: galaxies, stars, planets, and life forms have evolved. Biological evolution refers to the scientific theory that living things share ancestors from which they have diverged: Darwin called it "descent with modification." There is abundant and consistent evidence from astronomy, physics, biochemistry, geochronology, geology, biology, anthropology, and other sciences that evolution has taken place.

As such, evolution is a unifying concept for science. The National Science Education Standards recognizes that conceptual schemes such as evolution "unify science disciplines and provide students with powerful ideas to help them understand the natural world," and recommends evolution as one such scheme. In addition, the Benchmarks for Science Literacy from the American Association for the Advancement of Science's Project 2061 and NSTA's Scope, Sequence, and Coordination Project, as well as other national calls for science reform, all name evolution as a unifying concept because of its importance across the discipline of science. Scientific disciplines with a historical component, such as astronomy, geology, biology, and anthropology, cannot be taught with integrity if evolution is not emphasized.

There is no longer a debate among scientists over whether evolution has taken place. There is considerable debate about how evolution has taken place: the processes and mechanisms producing change, and what has happened during the history of the universe. Scientists often disagree about their explanations. In any science, disagreements are subject to rules of evaluation. Errors and false conclusions are confronted by experiment and observation, and evolution, as in any aspect of science, is continually open to and subject to experimentation and questioning.


The word "creationism" has many meanings. In its broadest meaning, creationism is the idea that a supernatural power or powers created. Thus to Christians, Jews, and Muslims, God created; to the Navajo, the Hero Twins created. In a narrower sense, "creationism" has come to mean "special creation": the doctrine that the universe and all that is in it was created by God in essentially its present form, at one time. The most common variety of special creationism asserts that

  • the earth is very young

  • life was originated by a creator

  • life appeared suddenly

  • kinds of organisms have not changed

  • all life was designed for certain functions and purposes.  

This version of special creation is derived from a literal interpretation of Biblical Genesis. It is a specific, sectarian religious belief that is not held by all religious people. Many Christians and Jews believe that God created through the process of evolution. Pope John Paul II, for example, issued a statement in 1996 that reiterated the Catholic position that God created, but that the scientific evidence for evolution is strong.

"Creation science" is an effort to support special creationism through methods of science. Teachers are often pressured to include it or synonyms such as "intelligent design theory," "abrupt appearance theory," "initial complexity theory,'' or "arguments against evolution" when they teach evolution. Special creationist claims have been discredited by the available evidence. They have no power to explain the natural world and its diverse phenomena. Instead, creationists seek out supposed anomalies among many existing theories and accepted facts. Furthermore, creation science claims do not provide a basis for solving old or new problems or for acquiring new information.

Nevertheless, as noted in the National Science Education Standards, "Explanations on how the natural world changed based on myths, personal beliefs, religious values, mystical inspiration, superstition, or

Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.

authority may be personally useful and socially relevant, but they are not scientific." Because science can only use natural explanations and not supernatural ones, science teachers should not advocate any religious view about creation, nor advocate the converse: that there is no possibility of supernatural influence in bringing about the universe as we know it.

Legal Issues

Several judicial rulings have clarified issues surrounding the teaching of evolution and the imposition of mandates that creation science be taught when evolution is taught. The First Amendment of the Constitution requires that public institutions such as schools be religiously neutral; because special creation is a specific, sectarian religious view, it cannot be advocated as "true," accurate scholarship in the public schools. When Arkansas passed a law requiring "equal time" for creationism and evolution, the law was challenged in Federal District Court. Opponents of the bill included the religious leaders of the United Methodist, Episcopalian, Roman Catholic, African Methodist Episcopal, Presbyterian, and Southern Baptist churches, and several educational organizations. After a full trial, the judge ruled that creation science did not qualify as a scientific theory (McLean v. Arkansas Board of Education, 529 F. Supp. 1255 (ED Ark. 1982)).

Louisiana's equal time law was challenged in court and eventually reached the Supreme Court. In Edwards v. Aguillard 482 U.S. 578 (1987), the court determined that creationism was inherently a religious idea and to mandate or advocate it in the public schools would be unconstitutional. Other court decisions have upheld the right of a district to require that a teacher teach evolution and not teach creation science: (Webster v. New Lennox School District #122, 917 F.2d 1003 (7th Cir. 1990); Peloza v. Capistrano Unified School District, 37 F.3d 517 (9th Cir. 1994)).

Some legislatures and policy-makers continue attempts to distort the teaching of evolution through mandates that would require teachers to teach evolution as "only a theory," or that require a textbook or lesson on evolution to be preceded by a disclaimer. Regardless of the legal status of these mandates, they are bad educational policy. Such policies have the effect of intimidating teachers, which may result in the de-emphasis or omission of evolution. The public will only be further confused about the special nature of scientific theories, and if less evolution is learned by students, science literacy itself will suffer.


American Association for the Advancement of Science (AAAS). 1993. Benchmarks for Science Literacy. Project 2061. New York: Oxford University Press.

Daniel v. Waters. 515 F.2d 485 (6th Cir., 1975).

Edwards v. Aguillard. 482 U.S. 578 (1987).

Epperson v. Arkansas. 393 U.S. 97 (1968)

Laudan, Larry. 1996. Beyond Positivism and Relativism: Theory, Method, and Evidence. Boulder, CO: Westview Press.

McLean v. Arkansas Board of Education. 529 F. Supp. 1255 (D. Ark. 1982).

National Research Council (NRC). 1996. National Science Education Standards. Washington, DC: National Academy Press.

National Science Teachers Association (NSTA). 1996. A Framework for High School Science Education. Arlington, VA: National Science Teachers Association.

NSTA. 1993. The Content Core: Vol. I. Rev. ed. Arlington, VA: National Science Teachers Association.

Peloza v. Capistrano Unified School District. 37 F.3d 517 (9th Cir. 1994).

Ruse, Michael. 1996. But Is It Science? The Philosophical Question in the Creation/Evolution Controversy. Amherst, NY: Prometheus Books.

Webster v. New Lennox School District #122. 917 F.2d 1003 (7th Cir. 1990).

Task Force Members

Gerald Skoog, Chair, College of Education, Texas Tech University, Lubbock, Texas

Randy Cielen, Joseph Teres School, Winnipeg, Manitoba, Canada

Linda Jordan, Science Consultant, Franklin, Tennessee

Janis Lariviere, Westlake Alternative Learning Center, Austin, Texas

Larry Scharmann, Kansas State University, Manhattan, Kansas

Eugenie Scott, National Center for Science Education, Berkeley, California

Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.

2. National Association of Biology Teachers Statement on Teaching Evolution4

As stated in The American Biology Teacher by the eminent scientist Theodosius Dobzhansky (1973), "Nothing in biology makes sense except in the light of evolution."5 This often-quoted assertion accurately illuminates the central, unifying role of evolution in nature, and therefore in biology. Teaching biology in an effective and scientifically-honest manner requires classroom discussions and laboratory experiences on evolution.

Modern biologists constantly study, ponder and deliberate the patterns, mechanisms and pace of evolution, but they do not debate evolution's occurrence. The fossil record and the diversity of extant organisms, combined with modern techniques of molecular biology, taxonomy and geology, provide exhaustive examples and powerful evidence for genetic variation, natural selection, speciation, extinction and other well-established components of current evolutionary theory. Scientific deliberations and modifications of these components clearly demonstrate the vitality and scientific integrity of evolution and the theory that explains it.

The same examination, pondering and possible revision have firmly established evolution as an important natural process explained by valid scientific principles, and clearly differentiate and separate science from various kinds of nonscientific ways of knowing, including those with a supernatural basis such as creationism. Whether called "creation science," "scientific creationism," "intelligent-design theory," ''young-earth theory" or some other synonym, creation beliefs have no place in the science classroom. Explanations employing nonnaturalistic or supernatural events, whether or not explicit reference is made to a supernatural being, are outside the realm of science and not part of a valid science curriculum. Evolutionary theory, indeed all of science, is necessarily silent on religion and neither refutes nor supports the existence of a deity or deities.

Accordingly, the National Association of Biology Teachers, an organization of science teachers, endorses the following tenets of science, evolution and biology education:

  • The diversity of life on earth is the outcome of evolution: an unpredictable and natural process of temporal descent with genetic modification that is affected by natural selection, chance, historical contingencies and changing environments.

  • Evolutionary theory is significant in biology, among other reasons, for its unifying properties and predictive features, the clear empirical testability of its integral models, and the richness of new scientific research it fosters.

  • The fossil record, which includes abundant transitional forms in diverse taxonomic groups, establishes extensive and comprehensive evidence for organic evolution.

  • Natural selection, the primary mechanism for evolutionary changes, can be demonstrated with numerous, convincing examples, both extant and extinct.

  • Natural selection—a differential, greater survival and reproduction of some genetic variants within a population under an existing environmental state—has no specific direction or goal, including survival of a species.

  • Adaptations do not always provide an obvious selective advantage. Furthermore, there is no indication that adaptations—molecular to organismal—must be perfect: adaptations providing a selective advantage must simply be good enough for survival and increased reproductive fitness.

  • The model of punctuated equilibrium provides another account of the tempo of speciation in the fossil record of many lineages: it does not refute or overturn evolutionary theory, but instead adds to its scientific richness.

  • Evolution does not violate the second law of thermodynamics: producing order from disorder is possible with the addition of energy, such as from the sun.

  • Although comprehending deep time is difficult, the earth is about 4.5 billion years old. Homo sapiens has occupied only a minuscule moment of that immense duration of time.

  • When compared with earlier periods, the Cambrian explosion evident in the fossil record reflects at least three phenomena: the evolution of animals with readily fossilized hard body parts; Cambrian environment (sedimentary rock) more conducive to preserving fossils; and the evolution from pre-Cambrian forms of an increased diversity of body patterns in animals.

  • Radiometric and other dating techniques, when used properly, are highly accurate means of establishing dates in the history of the planet and in the history of life.

  • In science, a theory is not a guess or an approximation but an extensive explanation developed from well-documented, reproducible sets of experimentally-derived data from repeated observations of natural processes.

  • The models and the subsequent outcomes of a scientific theory are not decided in advance, but can be, and often are, modified and improved as new empirical evidence is uncovered. Thus, science is a constantly self-correcting endeavor to understand nature and natural phenomena.  

Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.
  • Science is not teleological: the accepted processes do not start with a conclusion, then refuse to change it, or acknowledge as valid only those data that support an unyielding conclusion. Science does not base theories on an untestable collection of dogmatic proposals. Instead, the processes of science are characterized by asking questions, proposing hypotheses, and designing empirical models and conceptual frameworks for research about natural events.

  • Providing a rational, coherent and scientific account of the taxonomic history and diversity of organisms requires inclusion of the mechanisms and principles of evolution.

  • Similarly, effective teaching of cellular and molecular biology requires inclusion of evolution.

  • Specific textbook chapters on evolution should be included in biology curricula, and evolution should be a recurrent theme throughout biology textbooks and courses.

  • Students can maintain their religious beliefs and learn the scientific foundations of evolution.

  • Teachers should respect diverse beliefs, but contrasting science with religion, such as belief in creationism, is not a role of science. Science teachers can, and often do, hold devout religious beliefs, accept evolution as a valid scientific theory, and teach the theory's mechanisms and principles.

  • Science and religion differ in significant ways that make it inappropriate to teach any of the different religious beliefs in the science classroom.  

Opposition to teaching evolution reflects confusion about the nature and processes of science. Teachers can, and should, stand firm and teach good science with the acknowledged support of the courts. In Epperson v. Arkansas (1968), the U.S. Supreme Court struck down a 1928 Arkansas law prohibiting the teaching of evolution in state schools. In McLean v. Arkansas (1982), the federal district court invalidated a state statute requiring equal classroom time for evolution and creationism.

Edwards v. Aguillard (1987) led to another Supreme Court ruling against so-called "balanced treatment" of creation science and evolution in public schools. In this landmark case, the Court called the Louisiana equal-time statute "facially invalid as violative of the Establishment Clause of the First Amendment, because it lacks a clear secular purpose." This decision—"the Edwards restriction''—is now the controlling legal position on attempts to mandate the teaching of creationism: the nation's highest court has said that such mandates are unconstitutional. Subsequent district court decisions in Illinois and California have applied "the Edwards restriction" to teachers who advocate creation science, and to the right of a district to prohibit an individual teacher from promoting creation science, in the classroom.

Courts have thus restricted school districts from requiring creation science in the science curriculum and have restricted individual instructors from teaching it. All teachers and administrators should be mindful of these court cases, remembering that the law, science and NABT support them as they appropriately include the teaching of evolution in the science curriculum.

References and Suggested Reading

Clough, M. 1994. Diminish students' resistance to biological evolution. American Biology Teacher 56(Oct.):409–415.

Futuyma, D. 1997. Evolutionary Biology. 3rd ed. Sunderland, MA: Sinauer Associates, Inc.

Gillis, A. 1994. Keeping creationism out of the classroom. BioScience 44:650–656.

Gould, S. 1994. The evolution of life on the earth. Scientific American 271(Oct.):85–91.

Gould, S. 1977. Ever Since Darwin: Reflections in Natural History. New York: W.W. Norton.

Mayr, E. 1991. One Long Argument: Charles Darwin and the Genesis of Modern Evolutionary Thought. Cambridge, MA: Harvard University Press.

McComas, W., ed. 1994. Investigating Evolutionary Biology in the Laboratory. Reston, VA: National Association of Biology Teachers.

Moore, J. 1993. Science as a Way of Knowing: The Foundation of Modern Biology. Cambridge, MA: Harvard University Press.

National Center for Science Education, P.O. Box 9477, Berkeley, CA 94709. Numerous publications such as Facts, faith and fairness: Scientific creationism clouds scientific literacy by S. Walsh and T. Demere.

Numbers, R. 1993. The Creationists: The Evolution of Scientific Creationism. Berkeley, CA: University of California Press.

Weiner, J. 1994. The Beak of the Finch: A Story of Evolution in Our Time. New York: Alfred A. Knopf.

Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.

3. Resolution passed by the American Association for the Advancement of Science Commission on Science Education6

The Commission on Science Education of the American Association for the Advancement of Science, is vigorously opposed to attempts by some boards of education, and other groups, to require that religious accounts of creation be taught in science classes.

During the past century and a half, the earth's crust and the fossils preserved in it have been intensively studied by geologists and paleontologists. Biologists have intensively studied the origin, structure, physiology, and genetics of living organisms. The conclusion of these studies is that the living species of animals and plants have evolved from different species that lived in the past. The scientists involved in these studies have built up the body of knowledge known as the biological theory of the origin and evolution of life. There is no currently acceptable alternative scientific theory to explain the phenomena.

The various accounts of creation that are part of the religious heritage of many people are not scientific statements or theories. They are statements that one may choose to believe, but if he does, this is a matter of faith, because such statements are not subject to study or verification by the procedures of science. A scientific statement must be capable of test by observation and experiment. It is acceptable only if, after repeated testing, it is found to account satisfactorily for the phenomena to which it is applied.

Thus the statements about creation that are part of many religions have no place in the domain of science and should not be regarded as reasonable alternatives to scientific explanations for the origin and evolution of life.

Resolution on Inclusion of the Theory of Creation in Science Curricula7

WHEREAS some State Boards of Education and State Legislatures have required or are considering requiring inclusion of the theory of creation as an alternative to evolutionary theory in discussions of origins of life, and

WHEREAS the requirement that the theory of creation be included in textbooks as an alternative to evolutionary theory represents a constraint upon the freedom of the science teacher in the classroom, and

WHEREAS its inclusion also represents dictation by a lay body of what shall be considered within the corpus of a science.

THEREFORE the American Association for the Advancement of Science strongly urges that reference to the theory of creation, which is neither scientifically grounded nor capable of performing the roles required of scientific theories, not be required in textbooks and other classroom materials intended for use in science curricula.

Statement on Forced Teaching of Creationist Beliefs in Public School Science Education8

WHEREAS it is the responsibility of the American Association for the Advancement of Science to preserve the integrity of science, and

WHEREAS science is a systematic method of investigation based on continuous experimentation, observation, and measurement leading to evolving explanations of natural phenomena, explanations which are continuously open to further testing, and

WHEREAS evolution fully satisfies these criteria, irrespective of remaining debates concerning its detailed mechanisms, and

WHEREAS the Association respects the right of people to hold diverse beliefs about creation that do not come within the definitions of science, and

WHEREAS creationist groups are imposing beliefs disguised as science upon teachers and students to the detriment and distortion of public education in the United States,

THEREFORE be it resolved that because "creationist science" has no scientific validity it should not be taught as science, and further, that the AAAS views legislation requiring "creationist science" to be taught in public schools as a real and present threat to the integrity of education and the teaching of science, and

Be it further resolved that the AAAS urges citizens, educational authorities, and legislators to oppose the compulsory inclusion in science education curricula of beliefs that are not amenable to the process of scrutiny, testing, and revision that is indispensable to science.



Reprinted with permission from NSTA Publications, copyright 1997 from NSTA Handbook, 1997–98, National Science Teachers Association, 1840 Wilson Boulevard, Arlington, VA 22201-3000.


Statement on Teaching Evolution, National Association of Biology Teachers (NABT). Adopted by the NABT Board of Directors on March 15, 1995.


Dobzhansky, T. 1973. Nothing in biology makes sense except in the light of evolution. American Biology Teacher 35:125–129.


American Association for the Advancement of Science (AAAS), Commission on Science Education. October 13, 1972.


Adopted by AAAS Council on December 30, 1972.


Adopted by the AAAS Board of Directors on January 4, 1982, and by the AAAS Council on January 7, 1982.

Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.
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Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.
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Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.
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Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.
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Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.
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Suggested Citation:"Appendix C." National Academy of Sciences. 1998. Teaching About Evolution and the Nature of Science. Washington, DC: The National Academies Press. doi: 10.17226/5787.
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Teaching About Evolution and the Nature of Science Get This Book
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Today many school students are shielded from one of the most important concepts in modern science: evolution. In engaging and conversational style, Teaching About Evolution and the Nature of Science provides a well-structured framework for understanding and teaching evolution.

Written for teachers, parents, and community officials as well as scientists and educators, this book describes how evolution reveals both the great diversity and similarity among the Earth's organisms; it explores how scientists approach the question of evolution; and it illustrates the nature of science as a way of knowing about the natural world. In addition, the book provides answers to frequently asked questions to help readers understand many of the issues and misconceptions about evolution.

The book includes sample activities for teaching about evolution and the nature of science. For example, the book includes activities that investigate fossil footprints and population growth that teachers of science can use to introduce principles of evolution. Background information, materials, and step-by-step presentations are provided for each activity. In addition, this volume:

  • Presents the evidence for evolution, including how evolution can be observed today.
  • Explains the nature of science through a variety of examples.
  • Describes how science differs from other human endeavors and why evolution is one of the best avenues for helping students understand this distinction.
  • Answers frequently asked questions about evolution.

Teaching About Evolution and the Nature of Science builds on the 1996 National Science Education Standards released by the National Research Council—and offers detailed guidance on how to evaluate and choose instructional materials that support the standards.

Comprehensive and practical, this book brings one of today's educational challenges into focus in a balanced and reasoned discussion. It will be of special interest to teachers of science, school administrators, and interested members of the community.


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