This study examined the predictive relationship of fifth-, sixth-, seventh-, and eighth-grade students' final numerical grades for mathematics and communication arts (e.g., English or language arts) and their standardized scores on the Missouri Assessment Program (MAP). It examined the relationship between students' performance on the MAP in the areas of communication arts and mathematics over a 4-year period. Also this study examined how students' MAP standard scores from the previous year can predict their MAP standard scores for the current year. The sample for this study included a cohort of 86 middle school students from two different Missouri school districts. The dependent variables included final numerical grades, students' performance on the MAP assessments over a 4-year period, and students' standardized MAP assessment scores for the current school year. The independent variables included final numerical grades, student groups (i.e., with 4 related student groups, where each student has been successfully promoted to the next grade level), and students' standardized MAP assessments from the previous school years. A series of linear regression analyses was used to determine the predictive relationship between final numerical grades and students' standardized MAP scores. Students' final numerical grades were significant predictors of their performance on the MAP assessment in both communication arts and mathematics. Repeated measures ANOVA were used to determine if there were a mean difference in students' performance on the MAP based on their MAP standardized scores over a 4-year period in the areas of communication arts and mathematics. Significant differences were found between the mean difference in students' performance on the MAP assessment based on their MAP standardized scores over a 4-year period. Finally, a series of linear regression analyses was used to determine the predictive relationship between and students' standardized MAP scores from the previous school year and the current school year in communication arts and mathematics. Significant differences were found using students' standardized MAP scores from the previous school year to predict their MAP score for the current school year in both communication arts and mathematics. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]