Science Education

U.S. Teachers Evolving on Science of Evolution

• By Dian Schaffhauser
• 08/03/20

A survey done in 2007 found that only a third of public high school biology teachers were able to present the subject of evolution in a way that satisfied national science experts. And 13 percent of teachers offered creationism as a "valid scientific alternative" to evolution.

Twelve years later, teaching practices related to evolution are much better, according to a recently published report. The researchers found "substantial reductions" in creationist instruction and a "substantial increase" in the time that high school teachers devote to human evolution and the evolutionary process in general. The findings were published in the journal Evolution: Education and Outreach. The researchers came from Penn State University and the National Center for Science Education.

Why the uptake in more scientifically astute instruction? The researchers pointed to three changes:

• Broad adoption of the Next Generation Science Standards or state standards that borrow heavily from NGSS;

• Improvements in pre-service teacher education; and

• Changing practices of in-service teachers through improved professional development.

The project analyzed data from the "Survey of American Science Teachers" which was done between February and May 2019. While the survey included both high school and middle school samples, this report relied on high school responses, in particular.

In both surveys more than 95 percent of high school biology teachers reported covering evolution to some degree. But there was a 60 percent increase in the average number of class hours devoted to human evolution in the 2019 survey, an increase from 4.1 hours to 7.7 hours.

Also, there was "considerable movement" in how teachers responded to a question asking them whether they "emphasize the broad consensus that evolution is a fact, even as scientists disagree about the specific mechanisms through which evolution occurred." The share of teachers who disagreed with that statement declined from 22 percent to 13 percent, and the percentage who agreed grew from 74 percent to 79 percent. Those who "strongly agreed" rose from 30 percent to 47 percent.

The proportion of teachers who reported discussing creationism and intelligent design in classes dropped from 23 percent to 14 percent. And where it was discussed, the researchers pointed out, "some teachers may raise the topic of creationism in the context of explaining why it is not scientific." To understand responses better, the survey included two additional questions:

• "I emphasize that intelligent design is a valid, scientific alternative to Darwinian explanations for the origin of species"; and

• "I emphasize that many reputable scientists view creationism or intelligent design as valid alternatives to Darwinian theory."

The number of teachers disagreeing with the first statement rose from 32 percent to 58 percent, a change "largely driven by a sharp drop in the number of teachers who declined to answer this question," from 53 percent to 29 percent. And there was a big increase "in the percentage of teachers strongly disagreeing with each statement." The researchers interpreted that to mean that "more teachers are confident in their acceptance of evolution and rejection of creationism."

Overall, the researchers concluded, the NGSS and its influence in science-related learning standards, has influenced the instruction. Also, they noted, "new teachers who entered the profession after 2007 are doing an especially good job, as measured by their reports of their teaching practices with regard to evolution and creationism." Teachers with greater experience "have also improved on this score and have benefited from professional development opportunities on evolution, particularly if they work in NGSS-adopting states."

Yet, the report said there's still room for improvement. A sizable number of teachers "continue to either avoid evolution altogether or communicate mixed messages that can serve to legitimize non-scientific alternatives in the minds of their students," the researchers wrote. "Such teachers 'fail to explain the nature of scientific inquiry, undermine the authority of established experts, and legitimize creationist arguments, even if unintentionally.'" Those individuals "may play a far more important role in hindering scientific literacy in the United States than the smaller number of explicit creationists," the report stated.

The report is openly available on the Evolution: Education and Outreach website.