The purpose of this study was to examine the relationship among selected school funding variables, percentage of low socioeconomic status students, and student achievement. Funding variables included percentage of funds a school district received from the three primary sources: local, state, and federal. Additional funding variables included per pupil expenditures, as well as teacher salaries and administrative salaries. Student achievement variables included ACT composite, ACT math, ACT reading, and the percentage of students that met or exceeded state standards. The population studied consisted of Illinois school districts containing high schools. The data used was the data the Illinois State Board of Education provided to the Illinois Interactive Report Card. The years studied consisted of the data sets for the 2011, 2012, 2013 and 2014 school report cards. The concentration of low socioeconomic status students was found to have the strongest correlation to student achievement. Specifically, the greater the concentration of low socioeconomic students present in a district, the lower the student achievement scores. The second strongest indicator of student achievement was the percentage of funding that came from local sources or property taxes. Although schools with greater degrees of local source funding saw higher student achievement scores, the indicator's significance was not confirmed by linear regression. There was minimal correlation between student achievement and the average per pupil expenditure rate. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]