To develop a strong understanding of science, students in elementary and middle school should be encouraged to master a relatively small number of crucial concepts, and gradually expand their knowledge of those topics, a new study argues.
Released last week by the congressionally chartered National Research Council, the report says that too often, students are presented with long lists of disconnected facts and ideas, leaving them with no sense of what is most important and a poor understanding of the overall rules of science.
The report, is available from .
For years, educators have differed over whether students learn science more effectively through an empha-sis on hands-on experimentation or a more straightforward recitation of facts from teachers to students. The study, 鈥淭aking Science to School: Learning and Teaching Science in Grades K-8,鈥� says both approaches have merit, depending on the science topic.
It seeks to break new ground, however, in focusing more directly on science cognition, or how students learn. Research today, the authors of the study say, shows that focusing on a relatively small number of major concepts, and gradually building on them, works most effectively.
鈥淲e have a new and different understanding of how students learn in science,鈥� said Richard A. Duschl, a professor of science education at Rutgers University, in New Brunswick, N.J., who chaired the 14-member committee that produced the report. 鈥淲e need to find stronger themes, around which we can coordinate big ideas.鈥�
鈥楲earning Progressions鈥�
Decades of attempts to reform U.S. science education, dating to the 1950s, have yielded only modest im-provements in student performance on national tests and, most troubling to many observers, on compari-sons between the United States and other nations, the report says. A new, more focused strategy is needed, it contends.
While the 348-page report does not list the core science topics that students should master, it offers a few examples of likely building blocks, such as the theory of evolution and the study of atoms and molecules.
And the report specifically touts the potential of 鈥渓earning progressions鈥� to improve student performance in science. Learning progressions are detailed descriptions of the order in which student should learn about various topics from grade to grade, based on what is known about their understanding upon entering school, and expectations for what they should know after a certain length of time.
鈥淎 lot of science concepts are tough,鈥� said Heidi A. Schweingruber, a senior program officer at the Na-tional Research Council and a co-director of the two-year study. 鈥淪tudents need a sustained experience in dealing with them over time.鈥�
One finding of the study is that science educators consistently underestimate students鈥� ability to grasp scientific concepts at ages as young as 4 to 6. That early scientific understanding can be expanded quickly, the report says.
鈥淭he commonly held view that young children are concrete and simplistic thinkers is outmoded,鈥� it says.
Tasks to Master
At the same time, students from different economic backgrounds and with different English-language ability have varying levels of exposure to science, the authors note. Teachers can adjust instruction to account for those differences, the authors say, without sacrificing the rigor of their lessons.
Scientists often voice frustration over the public鈥檚 lack of understanding of the basic rules and standards of science鈥攄iscontent that has resurfaced during recent furors over the teaching of evolution and 鈥渋ntelli-gent design鈥� in public schools.
The NRC report seems to address the perceived shortcomings in public knowledgeby identifying four tasks that all students should master. Students, the report says, should develop the ability to know and interpret scientific explanations of the natural world; generate and evaluate scientific evidence; understand the development of scientific knowledge; and learn to participate productively in scientific practices and discussions.
State standards in science, or expectations for what students need to know by grade, should be stream-lined to focus on fewer topics, the authors argue. To accomplish that goal, they say, the paring-down of ideas also needs to occur in two prime reference documents used by state officials in crafting their stan-dards: the National Research Council鈥檚 1996 鈥淣ational Science Education Standards,鈥� and the 1993 鈥淏enchmarks for Science Literacy,鈥� from the American Association for the Advancement of Science.
Lawrence S. Lerner, a professor emeritus of physics and astronomy at California State University-Long Beach, who has studied state science standards and been critical of them, commended the study鈥檚 authors for recognizing that students can tackle many science topics in earlier grades鈥攁nd for saying that educa-tors have consistently set the bar too low.
But he was more circumspect about asking K-8 science teachers to focus more narrowly on certain ideas in their classes. That approach often serves as an excuse to lower expectations for students, he argued.
鈥淚t鈥檚 very easy for teachers to fool themselves and their students and say, 鈥楲ets focus on the big picture and not the details,鈥� 鈥� Mr. Lerner said. 鈥淒epth and breadth go together.鈥�
The study also recommends reorganizing local, state, and federal teacher-training programs to focus on core concepts in science, as well as building teachers鈥� understanding of the rules and practices of science. That approach would be a departure from 鈥渨hat virtually all active teachers learned in college,鈥� the report says, 鈥渁nd what most colleges teach aspiring teachers today.鈥�
