The "Science Assessment and Item Specifications for the 2009 NAEP (National Assessment of Educational Progress)" (the "Specifications") translates the "Science Framework for the 2009 NAEP" (the "Framework") into guidelines for developing items and for developing the assessment as a whole. The primary purpose of the "Specifications" is to provide the National Center for Education Statistics (NCES) and the NAEP assessment development contractor with information to ensure that the NAEP Science Assessment reflects the intent of the National Assessment Governing Board's (NAGB) science framework development process. The "Specifications" are structured so that the assessment developer and item writers have a single document to which to refer when they are working on the assessment. Therefore, portions of the "Framework" that specify characteristics of the assessment or items are repeated in the "Specifications". Portions of the "Specifications" are drawn from and informed by the 1996-2005 "Science Assessment and Exercise Specifications for the National Assessment of Educational Progress" and the "2005 NAEP Mathematics Assessment and Item Specifications". The extensive "Appendices" include lists of members of the Steering Committee and Planning Committee, the Steering Committee's guidelines for development of the "Framework" and "Specifications," NAEP Science preliminary achievement level descriptions, sample items and scoring guides, additional special studies, examples of generating and interpreting items, detail on learning progressions, and the NAEP Item Development and Review Policy Statement. (Contains 4 figures, 33 tables, 49 footnotes, and a bibliography.) [This document has been developed by WestEd and the Council of Chief State School Officers under contract to the National Assessment Governing Board (Contract # ED04CO0148).]