Washington--Taking a step officials said could greatly accelerate reform in science instruction and assessment, the National Assessment Governing Board this week will consider a major change in the way it tests students in that subject.
The plan for the 1994 science assessment, approved by a board committee last week, is being closely watched by science educators and assessment experts.
It reflects, they said, the first national standards in science, at a time when national officials are considering developing standards in all subjects. In addition, they noted, the document could form the basis for the first state-by-state assessment in science, if the Congress approves the Bush Administration’s proposal to conduct a third state-level assessment in 1994.
“I expect much of the 1994 naep,” Edward Hessler, science supervisor for the Minnesota Department of Education, wrote to the plan’s drafters. “One of my expectations is that this document can help bring us, some kicking and screaming, into a new assessment future.”
Open-Ended Questions “
In contrast to previous naep science tests, the 1994 framework calls for substantial use of hands-on materials, particularly in the 4th grade, and for test items that probe students’ understanding of themes that cut across science disciplines.
It also recommends some new assessment techniques--including a special study analyzing portfolios of student work in science--aimed at gauging students’ abilities over extended periods of time.
And it proposes a large increase in the use of open-ended questions, although not as much as the framework’s planning committee had proposed. While that panel had recommended that no more than 30 percent of test-takers’ time be spent on multiple-choice items, the board’s science committee voted last week to raise the cap to 50 percent.
Thomas Sachse, director of the science and mathematics division in the California Department of Public Instruction and a member of the planning committee, said the science panel’s action could weaken the assessment by encouraging too much instruction on lower-level tasks.
“In all the discussion of alternative assessments,” he said, “we want to have an assessment more of a mirror of the type of instruction we want.
“I’d hate to think half the time in science instruction [would be spent on] recognizing answers to questions,” Mr. Sachse said.
Conceptual Understanding
The framework for the 1994 science assessment was developed under contract to the nagb by the Council of Chief State School Officers along with the National Center for Improving Science Education and American Institutes for Research.
It is the third subject area to undergo a thorough overhaul by naep . The 1990 math assessment, the results of which were reported last month, and the 1992 reading assessment also represent dramatic breaks from the past naep and reflect reforms in the field.
The science framework was prepared by a 14-member planning committee, chaired by Senta A. Raizen, a specialist at the science center, and composed of leading science educators. Their work was overseen by a steering committee composed of representatives of education and science groups. The entire process was led by Richard Clark, a former state science official in Minnesota.
The framework states that the traditional approach to science teaching and assessment, which stresses rote memorization, must change to emphasize conceptual understanding and application of science knowledge and skills.
“Science education,” a draft of the document states, “is best served when students understand and can discuss ideas rather than memorizing definitions and accumulating unconnected facts.”
To measure such skills, the frame work proposes that the naep assessment evaluate students’ abilities to “know and do science.” At each grade level, it proposes, 45 percent of a student’s score would be devoted to “conceptual understanding"; 30 per cent in grades 8 and 12 would be based on scientific investigation; and 25 percent on practical reasoning, or solving problems by applying knowledge and skills.
Because of the heavy emphasis on hands-on learning in the early grades, the framework states that, in grade 4, 45 percent should be based on investigation, and 10 per cent on practical reasoning.
Too Much Technology?
The framework also proposes dividing test items equally in grades 4 and 12 among the physical, life, and earth sciences. However, it says, in grade 8, 40 percent of the items should be on the life sciences, because of the growing emphasis on “human biology” in middle-grades curricula.
At least 15 percent of the test’s content, the framework proposes, should deal with the “nature of science,” including the historical development of science and technology, the “habits of mind” of the field, and the methods employed by scientists and technicians. Nearly half of such questions should deal with technology, the framework says.
Bill G. Aldridge, executive director of the National Science Teachers Association and a member of the planning committee, said the emphasis on technology, which many educators have advocated to make the subject more relevant to students’ lives, may be excessive.
“We’ve failed to educate kids in science; they hate it,” he said. “The problem is we’ve done a lousy job teaching it. Disguising it in fanciful applications isn’t going to make it more palatable if it’s badly taught.”
The framework also recommends that a third of the test in grade 4, and half the test in the upper grades, should measure three themes--models, systems, and patterns of change--that cut across science disciplines.
Mr. Sachse of California, where the state science framework places a greater emphasis on themes and less on the separate disciplines, said the balance between the two in the naep guidelines is appropriate, since few schools have begun to teach the subject in that way. In addition to recommending new types of content for the assessment, the framework proposes new types of assessment methods to measure students’ abilities in science.
At least 30 percent of students’ time in all grades, the document says, should be on items that involve hands-on materials. But the nagb science committee reduced the amount of non-multiple-choice items on the assessment.
Portfolios To Be Studied
Daniel Taylor, associate director of the board, defended the lower limit. He said psychometricians are still uncertain about the validity and reliability of alternative assessment methods. In addition, he said, because of the limits on students’ time, the assessment could include too few open-ended questions to enable researchers to draw much information about student performance.
Even with the reduction, he noted, the amount of open-ended items on the 1994 science assessment will be far greater than on previous naep assessments.
In addition, the panel agreed to a special study in which naep would collect a portfolio of student work in science for a subset of the tested population. Naep is experimenting with a similar portfolio on the 1992 reading assessment.
Ms. Raizen of the national science center said the portfolio offers a way to tap student abilities not measured on a timed test, and is consistent with the goal of the assessment.
“It’s critically important that the assessment approach the way science ought to be taught,” she said. “We will build on the test technology that exists, but we’ve also got to test kids on things that are critically important.”
