This study investigates the correlation between food insecurity, educational achievement, and health among kindergarten children in the United States. Data from the Early Childhood Longitudinal Study—Kindergarten Cohort are used to analyze educational achievement and physical growth of kindergartners faced with food insecurity. The results demonstrate that children begin to experience the effects of food insecurity even at the most marginal level of household food deprivation. Children in households with any signs of food insecurity score lower and learn less during the school year.