This study examines socioeconomic status (SES), English language proficiency (ELP), vocabulary proficiency (VP), and math proficiency (MP) of students to determine if SES, as determined by the Free and Reduced Lunch Program (FRL), as well as English language proficiency (ELP) and vocabulary proficiency (VP), as measured by CELLA scale scores and subtests, impacts math performance on the geometry EOC exam scale scores. An ex-post facto multiple regression study is conducted using secondary data from a random stratified sample of a population of students from four school districts across southwest Florida. The study utilizes ELL groups which differed on independent variables (SES and CELLA scale scores and subtests) and test hypotheses about differences on dependent variables (geometry EOC scale scores). The ex post facto research begins with the results of geometry EOC scale scores, working backward to attempt to identify why students earned the CELLA scale scores and subtest results. Comparisons are made among the ELL students on SES and different subtests of the CELLA exams. Subtests include data on speaking, reading, writing and listening skills. These results could possibly help explain why students struggle with vocabulary and math performance. [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.]