There were two main goals this paper set out to accomplish. The first was to set up an econometric model that analyzed and predicted average ITBS test scores for school districts across Iowa. The ITBS test is a test which is mandated by the No Child Left Behind Act. It is used to judge how well schools are performing. The econometric model designed in this study predicted student achievement as a function of daily attendance rates, per pupil expenditures, dropout rates, student-to-teacher ratios, number of pupils per computer, average number of years experience for full-time teachers, average salary for full-time teachers, percentage of full-time teachers who have obtained a Master's degree or above for their educational level, percentage of district students who are either Hispanic, American Indian, African American, or Asian, and the percentage of children ages five to seventeen in families living in poverty for any particular school district. The second objective of this study was to analyze how different enrollment ranges affect various characteristics for school districts. The statistical averages were computed for these characteristics and put into a table to be more easily analyzed. A special note of emphasis was put into how average ITBS scores were affected by different enrollment ranges.