The National Assessment of Educational Progress (NAEP) is a survey of U.S. student knowledge and skills in different subjects at grades four, eight, and 12. NAEP combines samples of performances to provide information about the knowledge and skills of students in the United States as a whole, in each participating state, and in different demographic groupings. The report aims to increase understanding of the achievement levels for the National Assessment of Educational Progress: what they are, and what they are not. It is a reference for the U.S. public, particularly educators, parents, students, and policymakers. Seven booklets make up the report. Each booklet focuses on one of the subjects for which NAEP achievement levels have been set. This booklet focuses on U.S. history. Information in the booklet can be helpful in interpreting accurately the meaning of the U.S. history NAEP achievement levels and student performance relative to the levels. Achievement levels are: basic, proficient, and advanced. The report explains that there are three parts to NAEP achievement levels: (1) descriptions; (2) cutscores; and (3) sample items. It further explains that the achievement level descriptions are statements of what students should know and be able to achieve at each level. The cutscores represent the minimum score required for performance at each NAEP achievement level and are usually reported along with the percentage of students who scored at or above the level. Sample items provide illustration of student knowledge and skills required within each level of achievement. (BT)