Measures and Subscales
Subscales are constituent parts of an overall subject composite scale. For example, for Science through 2005, the subscales include earth science, life science, and physical science. The weighted average of these is the basis for the science composite scale, as described in the science framework.
When new frameworks are approved, the subscales may change. For instance, in the 2009 Science framework, the earth science subscale became earth and space sciences. Changes in subscales will be obvious in NDE if you select subscales for a subject for which they have changed.
If you need results for one or more subscales of a subject, realize that there are not as many data for them because the student samples are smaller.
Subscales are not reported for Civics, Music, Visual Arts, or Writing, but are reported for these six subjects: Economics, Geography, Mathematics, Reading, Science, and U.S. History. Subscales are not available for long-term trend NAEP.
To get details about subscales for any subject, see the framework for that subject http://nces.ed.gov/nationsreportcard/frameworks.asp.
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