The purpose of this sequential mixed method study was to examine the relationship between classroom climate and student achievement of middle school students. This study included a review of data collected from the Learning Environment Inventory from a purposeful sample of middle school students from a large suburban school district. A purposeful sample of students in grades 6-8 were also interviewed in an attempted to provide a more in-depth understanding of the potential influence of classroom climate factors on student achievement. Quantitative data were analyzed using frequencies, percentage, and Pearson's product moment correlations (r), while an inductive coding process was used to analyze the collected qualitative data. Quantitative analysis demonstrated that there was not a significant mean difference between classroom climate and student achievement. The qualitative analysis supported evidence from current research related to the topic that a positive relationship does exist between the two factors. [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.]