In 2009, the government administered the NAEA (National Assessment of Educational Achievement) to all-inclusive students for the target grades from elementary to high school. Those changes expanded the goals of academic achievement assessment from "providing information to improve the curriculums and teaching-learning methods and controlling the quality of education" to "diagnosing the academic achievement levels of individual students and checking the accountability of school education. The purposes of this study were to analyze the all-inclusive results of 2009 NAEA, examine the academic achievement levels of the sixth, ninth, and tenth graders in five subjects (Korean, social studies, math, science, and English), and provide their implications for policy making. To be more specific, it would investigate the students' academic achievement levels according to school levels, regional sizes, municipal and provincial educational agencies (or local educational agencies), and subjects, offer descriptive information about the background variables with the responses of the newly developed student and school questionnaires in 2009, and analyze relations between academic achievement of each school level and student and school background variables.