Eighty, seventh grade students attending a suburban middle school in southern Connecticut participated in the study evaluating the effectiveness of computer based geography games on student motivation and achievement. Using Connecticut Mastery Test (CMT) Scores and baseline U.S.A scores as criteria to develop matched pairs, students were divided so that the control group played Sheppardsoftware.com's States Level 3 and the experimental group played States Level 6. According to the data collected, States Level 3 and States Level 6 are significantly effective instructional tools that students enjoyed playing. CMT scores in spatial reasoning did not prove strong predictors of students' performance whereas U.S.A. baseline testing was a strong indicator in two of three categories. Results support the use of computer-based games to increase student motivation and social studies achievement.