Although interventions to change nutrition policies, systems, and environments (PSE) for children are generally cost effective for preventing childhood obesity, existing evidence suggests that nutrition education curricula, without accompanying PSE changes, are more commonly implemented. This study aimed to estimate the societal costs and potential for cost-effectiveness of 3 nutrition education curricula frequently implemented in United States public schools for childhood obesity prevention. Using the Childhood Obesity Intervention Cost-Effectiveness Study (CHOICES) microsimulation model, which projects the costs, health care costs saved, and cases of obesity prevented for childhood obesity prevention interventions, the research team conducted threshold analyses for each curriculum, estimating the cost per quality-adjusted life-year for a range of hypothetical effects on child BMI to determine how large of an effect each curriculum would need to have to meet a cost-effectiveness threshold of $150,000 per quality-adjusted life-year. Three nutrition education curricula without PSE were identified from SNAP-Ed; none had evidence of an impact on obesity risk. From 2023 to 2032, the estimated implementation costs of the curricula nationwide ranged from $1.80 billion (95% upper interval: $1.79, $1.82 billion) to $3.48 billion (95% upper interval: $3.44, $3.51 billion). Each curriculum would have to reduce average child BMI by 0.10 kg/m² or more—an effect size that has not been reported by any of the 3 curricula, or by more comprehensive existing prevention programs—to be considered cost effective at this threshold. SNAP-Ed–endorsed nutrition education curricula alone are unlikely to be cost effective for preventing childhood obesity. Continued efforts to implement interventions with strong evidence for effectiveness, including PSE approaches, are needed.