Background: School feeding program (SFP) increases access to education and to better health. This study aims to evaluate the effects of SFP on physical growth, cognitive development, psychosocial behavior, and learning achievement of school children.

Methods: A quasi-experimental study was conducted. The intervention group included 903 pupils in the fifth grade receiving the school meal, while the control group included 886 pupils, matched for age and sex, without meal. The meal consisted of a pie made of flour fortified with vitamins A, B6, B12, C, thiamin, riboflavin, niacin, folate, calcium, iron, zinc, and phosphorus. Socioeconomic position, nutritional status, and dietary behavior were evaluated. Neuropsychological tests were done. Psychosocial behavior was rated and educational achievement was recorded. Post hoc and independent sample t tests were used to detect the association of the studied parameters with the intake of school snack.

Results: Children who took the meal had better scores on visual memory, auditory vigilance tests (9.71 ± 2.80 vs. 7.45 ± 3.25; 25.02 ± 3.36 vs. 10.82 ± 8.92, respectively, P < 0.001), the afternoon attention and working memory test (8.20 ± 2.21vs. 7.75 ± 3.05) (P < 0.001), but less score of externalizing behavior (P < 0.001) than the control group. No significant changes of children’s nutritional status were detected between the two groups. School meal was the main predictor of visual memory and auditory vigilance (P < 0.001), and was the strongest predictor of academic achievements when combined with family size and meals’ frequency (P < 0.001).