Content Knowledge
The following process was used to identify standards and benchmarks for science:
Identification of Significant Reports
The Third International Mathematics and Science Study (TIMSS), a large-scale, cross-national comparative study of math and science curricula, has made available to the public about two?thirds of the mathematics and science items administered to students in 1994?95. Of interest for this study were all items used for populations 1 and 2; for population 3, in keeping with the stated purpose of this study (see Process of this work), only literacy items were reviewed. The International Association for the Evaluation of Educational Achievement (IEA) published TIMSS Science Items: Released Set For Population 1 (Third and Fourth Grade) (1998d); TIMSS Science Items: Released Set For Population 2 (Seventh and Eighth grade) (1998e);and Released Item Set For the Final year of Secondary School: Mathematics and Science Literacy, Advanced Mathematics, and Physics (1998c). Finally, McREL has published a study entitled A Distillation of Subject-Matter Content For the Subject-Areas of Language Arts, Mathematics, and Science (Kendall, Snyder, Schintgen, Wahlquist, & Marzano, 1999). Researchers at McREL reviewed a selected set of highly rated state standards within each subject area, examining them for common content. The McREL analysis resulted in the identification of the significant subject-area content that consistently appeared within these top rated documents.
Selection of the Reference Document
Identification of Standards and Benchmarks
Science as inquiryA final area, "unifying concepts and processes," is not articulated for grade levels, but is intended for development across K-12 science education. Science information in NRC's document is articulated for K-12 at the category level, but not at the standard level. That is, each standard and its associated content appears only once, and at one level (K-4, 5-8, or 9-12). For example, in the physical sciences under the heading "Earth and space science," a standard with the topic "Objects in the sky" appears with two related standards at grades K-4 only; at grades 5-8, three standards are under that category, and a closely related topic is "Earth in the solar system." At grades 9-12, four standards cover the area, and the one nearest in content to "Earth in the solar system" or "Objects in the sky" is the "Origin and evolution of the universe." Thus, the 66 standards are closely related within six categories, but are not articulated across the grade ranges by standard. Since our model calls for the articulation of standards across grade levels wherever possible, some reorganization of content was necessary. Although in part the benchmarks were constructed into standards from "the ground up," there was strong guidance provided by the structure of standards available from Project 2061's Benchmarks for Science Literacy. At the benchmark level, Project 2061's Benchmarks proved very useful for distinguishing content at the grade ranges selected for this study: K-2, 3-5, 6-8, and 9-12. Material from the NRC reference document was added to or revised in four cases: 1) when minor modification of a benchmark statement allowed for additional citation support, 2) when the original statement carried more than one basic idea and was divided into components, 3) when stylistic changes helped the sense of the statement, and 4) when benchmark statements not in the science standards document were added because the information was found to appear consistently in the other major documents identified for science. Additionally, there were a few instances of content duplication across standards. In each case that the subject material appeared to be redundant across standards, it was also clear that the same benchmarks within a standard served the purpose of preparing students for more complex, related ideas at later benchmark levels. For this reason, the duplicates were not deleted as would otherwise be done, but cross-referenced in the citation log. (For more detail, see How the Subject-Area Sections are Structured.) It should be noted that content that appears in the science documents but is closely related to technology will be found incorporated into that section. Such topics as the interaction of technology with science and with society will now be found in the technology section.
Integration of Information from Other Documents
Any benchmark that addressed content closely related to a test item in the TIMSS science assessment has been identified by indicating the test level of the matching TIMSS assessment item. Similarly, any benchmark that addresses science content that was also identified as important in the McREL study of top standards documents has been so identified by an asterisk at the end of the citation log, which appears just above and to the right of the benchmark. |