The purpose of this study was to determine if any relationship existed between the change in developmental scale scores (DSS) on the Florida Comprehensive Assessment Test (FCAT) for reading and mathematics, in selected Florida school districts among charter and non-charter public high schools, for grades 9 and 10. This study also investigated if any relationship existed in student achievement based on student demographics (gender, economically disadvantaged, primary home language (ELL) and ethnicity), and examined if there was a difference in professional demographics of faculty (advanced degrees, teachers’ average years of teaching experience, and percent of courses taught by out of field teachers gender), among charter and non-charter public high schools in the state of Florida. School data were analyzed from 234 charter and non-charter public high schools, within 15 districts across the state of Florida, for the years 2007-2009. The findings of this research suggest charter high schools in the state of Florida are not keeping the pace with their traditional public high school counterparts. Over a three year period, charter high schools had significantly lower developmental scale scores on the FCAT, in both reading and mathematics, than non-charter public high schools. The findings also suggest that student demographics, with respect to male gender, economically disadvantaged, and ELL, combined with charter school status, negatively impact student achievement as measured by DSS. The disparity noted with regard to faculty demographics between charter and non-charter public high schools, only touches on some considerable differences between the two school iv types; more information is needed on the variations so parents and students can make informed choices. For future research, replication of this study with an expanded sample size of charter schools and a longer period of time for data collection was recommended. Separate studies are recommended on the differences between charter and non-charter public schools with regard to instructional time, curriculum or grade levels offered, the differences between parent and student perceptions, and the differences between funding and principal background as it relates to student achievement.