State science tests differ greatly in what they expect students to know about evolution, with some asking no questions about the theory and others including more than a dozen items related to it, an Education Week review has found.
Responses from more than 20 states to a survey on high school science assessments show that the vast majority of those states include at least one question that specifically refers to the term “evolution.” Just three states responding—Alabama, Ohio, and South Dakota—indicated that their exams offered no questions using that word.
The theory of evolution, pioneered most famously by Charles Darwin, posits that humans and other living creatures have descended from common ancestors over time through a process of random mutation and natural selection. It is widely considered to be a pillar of modern biology. Over the past year, however, public education has been roiled by high-profile disputes over whether schools should subject evolution to greater criticism or promote purported alternative explanations for life’s development, such as “intelligent design.”
What is tested is typically what is taught, research shows. And all states will have to give science tests to comply with the federal No Child Left Behind Act beginning in the 2007-08 school year.
No states surveyed by Education Week said their high school science assessments include questions about intelligent design, the idea that an unnamed force may have guided life’s development, or the biblically based belief known as creationism. The vast majority of scientists maintain that those concepts should not be considered science.
Similarly, none of the states surveyed said its statewide exams asked students about alleged weaknesses in evolution, or criticism of the theory, an approach that has been pushed by elected officials and interest groups around the country.
Read the related story,
Downloadedweek.org’s comprehensive coverage of the teaching of evolution in the nation’s schools.
“I would have been very disappointed” if alternatives had shown up on tests, said Senta Raizen, the director of the National Center for Improving Science Education, in Arlington, Va. “Science is based on observations concerning natural phenomena. Belief systems do not. They may be legitimate for people who hold those beliefs, but they’re not science.”
Ms. Raizen recently co-chaired a committee that directed the revision of the blueprint for the science portion of the National Assessment of Education Progress, perhaps the most closely scrutinized exam in the country, which influences many state assessments.
For its review, Education Week sent a list of questions to 29 states that, as of last school year, reported that they had science tests at the elementary, middle, and high school levels that were aligned with their state standards. The review focused on high school exams, the level at which evolution is typically taught in the greatest depth.
Of the 22 states that responded to the survey, 17 indicated they had at least one question that specifically mentioned evolution on the most recent exam, three states said they had none; one state, Kentucky, declined to answer the question; and another, Tennessee, said it was unlikely the term showed up in a question.
States tend to be protective of testing materials, mostly to ensure that the process remains tamper-proof. Thus, some states declined to say how many test items were connected to evolution.
Of those states that provided specifics, the number of questions on their high school science assessments that cited “evolution” as it pertains to biological changes in species ranged from zero to seven.
When asked how many questions related to evolution generally, without mentioning the word, some state officials said their tests included no such items, while others, such as New York and Utah, said they had as many as a dozen questions on the topic.
Test Deadlines Coming
In some ways, the contrasting approaches on evolution reflect different approaches in science testing overall.
Some of the states with the greatest number of evolution-related items give subject-specific tests in biology. Likewise, states with fewer of those questions test students across a broad range of scientific fields, such as physics and chemistry.
Twenty-two states responded to an Education Week survey about the extent to which they test students’ knowledge of evolution on high school science tests.
SOURCE: Education Week
In addition, the total number of test questions varies from a low of 30 to a high of 180. Half the states surveyed said they use only multiple-choice items.
States are facing new pressure to test students in science. The No Child Left Behind law requires states to have science assessments in place at three grade levels—3-5, 6-9, and 10-12—by the end of the 2007-08 academic year, and to have standards in those subjects in place by this school year. According to a recent survey by the Council of Chief State School Officers, 42 states have science tests in place at the three levels, though not all are aligned with their standards.
Experts on science testing were not surprised by the broad differences in how states treat evolution. Those disparities could be attributed not only to the different ways in which exams are structured, they said, but also to the dissimilar ways in which state standards cover the theory.
“It’s impossible to put an absolute number on what is the right number of questions to include about evolution,” said Meryl Bertenthal, a former program officer at the congressionally chartered National Research Council, who has studied state science testing. “The emphasis and the depth [will be] similar to the state standards. … You’re not likely to see questions that are not aligned with the standards.”
A related Education Week analysis, published last month, showed that state standards documents vary greatly in their coverage of evolution, with many ignoring core concepts and evidence connected to the theory. (Nov. 9, 2005.)
Alabama’s high school science assessment, which covers many science topics, does not include the term evolution, according to state officials’ survey responses. Yet references to the theory are found in underlying language throughout the state’s standards. The exam, however, is based on specific items in the standards that are highlighted as central concepts, said Gloria Turner, the state’s director of assessment, and evolution is not one of them.
“We assess the content standards as they are written,” she said.
‘Can’t Cover Everything’
In the past year, efforts to promote alternatives to evolution, or raise questions about its teaching, have played out in more than 30 states, according to the Oakland, Calif.-based National Center for Science Education, which monitors those fights.
One of the most visible battles has played out in the 3,600-student Dover, Pa., district, where the school board in 2004 approved a policy requiring that students be introduced to intelligent design. A federal lawsuit on the policy awaits a judge’s ruling. (Nov. 16, 2005.)
Another equally visible fight occurred in Kansas, where state school board members last month included more criticism of evolution in state science standards.
The effect of those changes is unclear. Kansas’ high school science test usually has four to six questions on evolution, out of 60 overall, and only those items would likely be affected, if state board members decided to revise their exam to reflect the new standards, said Alexa Posny, the state’s deputy education commissioner for learning services.
All questions on Kansas’ test, next administered in 2008, are multiple-choice. Ms. Posny was not sure how state officials might structure a multiple-choice question about criticism of evolution. “It would be a challenge,” she said.
South Dakota also does not mention evolution specifically on its high school test, though officials said two questions related to the concept more generally. That state, however, is in the process of developing a new test to meet requirements of the NCLB law, said Gay Pickner, South Dakota’s director of assessment. She did not know if the new test would include questions on evolution.
No questions on Ohio’s 38-question science assessment, administered this past spring, referred to biological evolution, state officials said. That test is based on Ohio’s state standards, which were revised in 2002 after an extended debate, to encourage critical analysis of evolution and broad coverage of the theory overall.
State and federal officials take a number of approaches in measuring students’ knowledge of evolution. Some, for example, specifically cite the term “evolution,” while others say they don’t have questions that mention the word.
NAEP: 12th grade science test, sample questions, 2000
Which of the following is NOT a part of Darwin’s theory of evolution by natural selection?
A) Individuals in a population vary in many ways.
B) Some individuals possess features that enable them to survive better than individuals lacking those features.
C) More offspring are produced than can generally survive.
D) Changes in an individual’s genetic material are usually harmful.
Alabama: Sample question, blueprint for state science test
Which of these is NOT an inherited trait that could help a species survive over time?
A) the shape of a finch’s beak
B) the thickness of a bear’s fur
C) a rabbit’s instinct for avoiding predators
D) a human’s resistance to disease by vaccination
(Correct answers are in bold.)
Deborah Owens Fink, an Ohio state school board member who supported those standards, was surprised that the concept did not appear on the state test. But she and other state officials noted that an original bank of potential questions included several evolution items. Those queries were eventually pared down to include randomly selected questions at various difficulty levels.
“If you only have 38 questions,” Ms. Fink said, “you can’t cover everything.”
Treatment in NAEP
While most states included only a few test items about evolution, that treatment is similar to the approach used on one of the most heavily scrutinized precollegiate tests in the country, the National Assessment of Educational Progress. On the 2005 version of the science NAEP, 12th graders were quizzed about four items that referred specifically to evolution and five others that covered related concepts, making up 4 percent of the 209 total questions.
NAEP also provides a glimpse of how well students performed when questioned about evolution. Fifty-one percent of the 12th graders picked the correct answer on a multiple-choice question from 2000 about different aspects of the concept.
By comparison, 61 percent correctly answered a question about sexual and asexual reproduction in animals.
In Utah, a state that reported having about 15 evolution-related items on its high school exam, 61 percent and 66 percent of students reached the “proficient” level on two different parts of the state biology test most directly related to evolution, while 67 percent who scored proficient on the overall exam. Students there are required to take at least two high school science tests; the biology exam is one option.
Utah officials have no inclination to include questions about intelligent design or other alternative views on their exam. “Those things don’t belong in science,” said Brett Moulding, the state’s director of curriculum.
Several experts on science education and testing said they fully expected that states were not testing students on views critical of evolution. They noted that precollegiate science teachers, who generally want evolution taught, often play a major role in shaping the content of tests.
“For the vast majority of biology teachers out there, there’s no controversy here. There’s no close call,” said Bruce A. Fuchs, the director of the office of education at the National Institutes of Health, an arm of the federal government. He speculated that any future efforts to promote alternatives to evolution in science testing were “likely to be forced in from the top,” if at all, “rather than coming from teachers.”