The trend and demand for virtual education has grown nationwide. With an increase in students choosing this type of education, inevitably the demand for schools of this type of educational instruction has increased in number. The purpose of this study is to determine the extent of the relationship between virtual school size and student achievement in virtual schools in a southwestern state. For the purpose of this study, achievement was measured by student performance on state testing scores. The study used descriptive and inferential statistics to analyze enrollment size and State of Texas Assessment of Academic Readiness (STARR) English Language Arts/Reading in Grades 5 and 8, Math in Grades 5 and 8, English I, English II, and Algebra I testing scores in regard to race and gender.