We investigated for all of the charter school districts (n = 192) in the State of Texas for the 2008-2009 school year the relationship between the 65% instructional expenditures ratio mandate and college-readiness rates in reading, math, and in both subjects for all high school students and then separately for African American, Hispanic, and White students. After determining that statistically significant relationships were present between instructional expenditures and college-readiness rates in reading, math, and in both subjects for all students, three groups of charter schools were created, based upon their instructional expenditures (i.e., less than 60% instructional expenditures, 60 to 64.99% instructional expenditures, and 65% instructional expenditures and higher). Statistically significant differences were yielded among these groups in students' college-ready rates in reading, math, and in both subject areas. School districts in the lowest group of instructional expenditures had the lowest percentages of students whose scores were college-ready in reading, math, and in both subject areas. As instructional expenditures increased, the student college-ready rates increased as well. Findings were consistent across the four groups of students whose scores were analyzed. Implications of these findings and suggestions for further research are discussed. (Contains 2 tables and 1 footnote.)