This study investigated the relationship between health conditions suffered over time and student scores on the Stanford Achievement Test 9 in Yuma County, Arizona, public grade schools. The majority of children in Yuma County were of Hispanic origin. The poverty and low income status of most of these children placed them at greater risk for health problems. The primary purpose of the study was to ascertain how the rate of math achievement of students who suffered from an illness or injury prior to testing compared to those students who had no known illness or injury. Findings suggested that physical illness influenced math achievement trajectories adversely. Importantly, the achievement gaps associated with several health conditions attenuated over time. However, children who experienced an injury or poisoning, or an endocrine, nutritional, or metabolic disease developed permanent math achievement deficits. (Contains 8 tables, 5 figures and 5 footnotes.)