From 2009 to 2014, school districts in Oklahoma faced the challenge of educating a growing population of students to high academic standards and increased accountability while state aid has been restricted to flat or negative levels annually. These circumstances have left many stakeholders concerned about the adequacy of education funding in Oklahoma. There is no evidence of empirical research into the issue of school funding adequacy in Oklahoma between the years of 2005 and 2015. Therefore, this study presents new knowledge about how district spending correlates with student achievement as an indication of the level of Oklahoma education funding adequacy. The results and conclusions provide perceptions of the current financial condition to assist the reader in judging whether changes are necessary to improve fiscal support for schools. This study incorporated the Successful School District model of analysis and binary logistic regression to discover how instructional and administrative expenditures related to high levels of academic achievement. The analysis compared two groups of school districts that were demographically similar yet displayed varying degrees of academic achievement in order to determine if there was a statistically significant difference in their spending.