State standards for academic content vary enormously in how well they cover the topic of evolution, with many of those documents either ignoring or giving scant treatment to the core principles of that established scientific theory, an Education Week analysis shows.
Nearly all the science standards reviewed at least mention the theory advanced most famously by Charles Darwin, as well as the related concept of natural selection. But many of those standards, the basic documents describing what students are expected to know, fail to address the fundamental evidence supporting the theory, which explains how life on Earth developed.
Many states’ standards, for instance, make little or no connection between the theory of evolution and established scientific evidence about the age of the Earth, internal similarities between organisms, or the common ancestry of different species.
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The findings emerge as the theory of evolution faces attacks in states and school districts across the country. Meanwhile, a closely watched federal trial on purported alternatives to its teaching is coming to an end in Harrisburg, Pa.
Education Week reviewed the science standards of a large majority of the states, comparing them against 10 concept statements about evolution in the National Science Education Standards, or NSES. That document, published by the congressionally chartered National Research Council in 1996, is widely regarded as a prime reference tool for what students should know about science. The review was conducted jointly with the Education Week Research Center, with the help of an independent computer database maintained by a nonprofit research organization called Align to Achieve. That database included complete versions of science standards from 41 states.
The review found that the vast majority of those state documents, or 39, offer some description of biological evolution and how it accounts for the diversity of species that exist today. Nearly as many of those standards, 35, give similar treatment to natural selection, Darwin’s principle that species evolve through the passing on of advantageous traits to their offspring. Overall, at least 25 states met at least half the 10 NSES concept statements for student understanding of evolution.
Yet state standards are less successful in addressing other important evolutionary principles, the analysis found. Fewer than half the states reviewed, or 20, describe the way that the internal structures and chemical processes of organisms provide evidence of their common ancestry.
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Table: Evolution Concepts
More detailed information on the research and methodology used for this story can be found in the EPE Research Center brief, “Evolution in State Science Education Standards.”
Only 21 states describe how random mutation or other changes in DNA and cells can affect evolution, and just 22 describe how the various mechanisms of evolution work. And only six states describe how long evolution has been producing diversity in organisms—through at least 3.5 billion years of the Earth’s history, most scientists say.
“I’m not impressed,” Wayne W. Carley, the executive director of the National Association of Biology Teachers, in Reston, Va., said of the results. “Evolution is the cornerstone and the building block of modern biology. It should be the centerpiece of modern biology education.”
Uneven Record
State standards play an influential role in shaping what students are taught in public schools. In many cases, the standards determine what questions students will encounter on standardized tests. They also shape the content of science textbooks, which publishers typically have written to align with the standards of the largest states.
Several states have augmented their science standards with reams of curricular materials and supplementary documents, which have provided more detailed descriptions of evolution and many other scientific concepts.
Some state officials contend that those secondary materials set more rigorous expectations for teachers and students than the standards themselves, which are aimed at providing relatively broad learning goals. Still, secondary curricular documents tend to receive much less public scrutiny than the actual standards. And in some cases, the secondary materials have not been subjected to a potentially exhaustive review by state school boards, legislatures, or other public entities.
“Standards represent a public consensus,” said Gerald Skoog, a retired education professor at Texas Tech University in Lubbock. Mr. Skoog is the former president of the National Science Teachers Association, and has studied science standards extensively. “They’ve gone through a political process.”
For decades, questions about evolution’s status in public school science classrooms have sprung up sporadically, but the issue has roiled states and districts anew in recent months. Many officials and residents are pushing to have students told of supposed weaknesses in the theory. The 3,600-student district in Dover, Pa., for instance, has sought to inform students of ideas such as “intelligent design” in addition to evolution, a policy that is now the subject of an ongoing federal lawsuit being heard in Harrisburg. Both sides concluded their arguments last week in that heavily scrutinized case. (“69ý Get Lessons in Government, Science During Trial on ‘Intelligent Design’,”Web Only Oct. 20, 2005.)
Intelligent design is the idea that an unidentified force may have guided various aspects of life’s development, which proponents argue is too complex to have arisen otherwise. The vast majority of scientists, however, reject intelligent design as an essentially religious and scientifically unverifiable belief, and say that evolution is, in fact, one of the most thoroughly tested explanations in science. Evolution posits that species develop over time, through natural selection and random mutation.
State standards, meanwhile, have grown increasingly important under the mandates of the federal No Child Left Behind Act. The nearly 4-year-old law requires states to have science standards in place by the end of this school year, and to begin testing students annually in that subject at three different grade spans—3-5, 6-9, and 10-12—by the end of 2007-08.
The NSES concepts selected by Education Week for its analysis were closely aligned with Benchmarks for Science Literacy, another widely respected set of standards, published in 1993 by the American Association for the Advancement of Science, or AAAS. Several states list one or both of those documents as having guided the development of their standards. States did not need to match the NSES wording exactly, or even approximately, to score well in the analysis; they needed only to address various concepts in general terms and connect them with evolution.
The analysis was completed by using a national database of standards created by Align to Achieve, an organization based in Cambridge, Mass., that conducts research on standards in various content areas. The review focused on 41 states with standards housed in Align to Achieve’s database.
That database includes only state-accepted standards—typically, documents that were approved by a state board of education or legislature—rather than supplementary materials. State standards are in near-constant flux, and some of the standards in the database have since been replaced by more recent versions.
One Word Missing
In its review, Education Week found four states—Florida, Illinois, Kentucky, and Oklahoma—that do not mention the term “evolution,” as it pertains to biological changes in species, anywhere in the body of their science standards.
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The Illinois Learning Standards for Science scored poorly in the analysis. Without employing the term “evolution,” they specify that students should be able to “describe processes by which organisms change over time,” using evidence from the fossil record and other sources. The other three states use similar substitute language.
Gwen Pollock, the principal state science education coordinator in Illinois, said that despite omitting the term from the standards, state officials in no way were suggesting that students shouldn’t master the concept.
She also noted that Illinois officials have produced separate documents, known as “performance descriptors,” that do mention evolution specifically. Those documents are meant to provide teachers and students with more detail about the material they will face on statewide assessments, Ms. Pollock said.
“There is accountability through the statewide assessment,” she said, adding that Illinois officials were “very confident” that students were learning about evolution.
Science Content Weak?
Education Week’s findings echo some of the conclusions of earlier studies of state standards and evolution. A 2000 study by the Washington-based Thomas B. Fordham Foundation found that roughly two-thirds of states did at least a satisfactory job of explaining evolution in their standards, but that individual states’ performance ranged from “excellent” to “disgraceful.”
Paul R. Gross, a professor emeritus of life sciences at the University of Virginia in Charlottesville, is leading a new Fordham study of state science standards, to be released soon, which includes a look at evolution language. He said his research was indicating that most state standards treated evolution “reasonably well,” though their quality varied greatly.
Mr. Gross also suggested that singling out evolution as a weak spot in state standards is misleading, because those documents lack academic depth across many areas.
“The handling of evolution is disappointing,” he said, “but the handling of science content overall is disappointing.”
Other states besides Illinois are also relying on secondary documents to describe evolution in greater detail than in the state standards themselves. Wisconsin’s Model Academic Standards for Science Instruction didn’t fare well in Education Week’s analysis, with descriptions of evolution that failed to provide detail comparable with the NSES concepts.
But Wisconsin officials are writing a new “assessment framework” that will describe evolution and other concepts in greater detail, said Shelley A. Lee, the state’s science education consultant. Wisconsin has also issued a statement describing evolution as a “fundamental and important” concept in science and has warned that attempts to teach religious belief in science class are illegal.
“You really have to look beyond the standards,” Ms. Lee said. She said she regularly points teachers and parents to the framework “for even greater specificity and clarity.”
Kentucky, which makes no mention of the term evolution in its standards, also scored poorly in Education Week’s overall analysis of coverage of the theory. State officials believe their standards should have fared better, arguing that the document clearly expects students to understand evolutionary concepts, even if the term isn’t mentioned. They also note that an additional guide for teachers and others, known as the “core content for assessment,” is being revised to include the term itself.
“It’s obvious to me—we support the teaching of evolution,” said Lisa Gross, a spokeswoman for the Kentucky education department. Including the specific term, she maintained, is less crucial than “teaching students how to learn.”
But Jo Ellen Roseman, the director of Project 2061, a long-standing enterprise at the AAAS to promote literacy in science, mathematics, and technology, dismissed efforts to describe evolution while dodging the term itself.
“‘Change over time’—that’s not evolution,” Ms. Roseman said. “We expect that students who graduate from high school will be able to read the term ‘evolution’ in the newspaper and know what it is.”
Glenn Branch, the deputy director of the National Center for Science Education, an Oakland, Calif., organization that opposes the teaching of intelligent design and creationism in science classes, agreed.
“It conveys the idea that there’s something menacing in the e-word,” Mr. Branch said of omitting the term. “It doesn’t do students a service to not use standard scientific terminology.”
Besides setting clear expectations for students, he added, standards serve another function: They are authoritative state documents teachers can rely on when confronted with outside pressure to teach creationism or intelligent design.
“Teachers who face irate parents can point to the state standards,” Mr. Branch said.
‘Secondary Battleground’
Several state officials explained the lack of detail about evolutionary theory by saying that standards should provide relatively broad learning goals for students—and secondary documents, more detailed language.
“State standards are more global statements,” said Dixie Stack, the director of curriculum in Maryland, which did relatively well in the analysis. Her state also offers a more detailed treatment of evolution in a curriculum document outside of the state standards. “We develop curriculum for teachers to know what students are expected to know about those global statements,” she said.
Mr. Carley of the biology teachers’ association, said that approach could work. “There are multiple layers at which evolution can expand or contract,” he said. “As long as it expands, that’s OK.”
But Mr. Branch of the center for science education warned that such supplementary documents were beginning to emerge as a “secondary battleground” in debates over evolution. Ohio’s state board of education, after a prolonged debate, approved revised science standards in 2002 that do not advocate intelligent design. That document is “not bad” in its overall treatment of evolution, Mr. Branch argued, and it scored well in Education Week’s overall analysis.
Yet after the furor subsided, Ohio officials in 2004 approved an additional science lesson plan titled “Critical Analysis of Evolution.” That document drew objections from many state and national science organizations.
One state that scored well in Education Week’s review, Rhode Island, relied extensively on the AAAS science standards in crafting its document. Closely following that model gave educators and others the detail they needed to shape classroom lessons, said Linda A. Jzyk, a science and technology specialist for the state.
“The more specificity we can provide, the better for all,” she said. “It helps the teacher in their daily practices, [and] it helps districts in shaping their curriculum.”
