This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance levels--basic and above, proficient and above, and advanced; (2) Background information about limitations of the state's test data and characteristics of the state's testing system, including major changes in its testing system; (3) Figures and tables with the percentages of students scoring at the proficient level and above for all years with comparable data since 1999 and for all grades tested under the No Child Left Behind Act; (4) Figures and tables with percentages of students performing at three achievement levels--basic, proficient, and advanced--for all years with comparable data and for grades 4, 8, and 10 (or adjacent grades, in the case of states that lack comparable trend data for these default grades); (5) Figures and tables with mean scale scores, standard deviations, and effect sizes for all years with comparable data and for the three grades analyzed in this study; and (6) Figures and tables with mean scale scores, standard deviations, and effect sizes for all years with comparable data and for the three grades analyzed in this study. Mississippi implemented new assessments at all grades in 2007-08. As a result, 2008 test data were not comparable to those from previous years. The trends described in this report are based on data from 2002 to 2007 (2003 to 2007 for high school). Results at the basic, proficient, and advanced levels were mixed, but test scores increased at most grade levels analyzed. Specific results include: (1) Between 2002 and 2007 (2003-2007 for high school), the percentage of students scoring at the basic level and above in reading increased slightly at the elementary and middle school grades analyzed and decreased slightly at the high school level; in math, the percentage of students at the basic level and above rose at a moderate-to-large rate at the elementary and middle school grades analyzed and at a slight rate at the high school level; (2) The percentage students performing at the proficient level and above in reading increased at a moderate-to-large rate at the elementary level, rose slightly at the middle school level, and decreased at a moderate-to-large rate at the high school level; in math, there were moderate-to-large gains in the percentage proficient at all three grade levels analyzed; and (3) The percentage of students reaching the advanced level in reading increased at a moderate-to-large rate at the elementary level, increased slightly at the middle school level, and decreased slightly at the high school level; in math, the percentage of advanced students showed a moderate-to-large increase at all three grade levels analyzed. (Contains 1 footnote, 6 figures and 6 tables.) [For "State Test Score Trends through 2007-08, Part I: Is the Emphasis on 'Proficiency' Shortchanging Higher- and Lower-Achieving Students?," see ED506121. For "State Test Score Trends through 2007-08. Part II: Is There a Plateau Effect in Test Scores?," see ED506122.]