This is a protocol for a Cochrane Review (intervention). The objectives are as follows:
1. To assess the effectiveness of school feeding programs for improving the physical and psychological health of children experiencing socioeconomic disadvantage across the world.
2. To compare the effectiveness of school feeding programs for children experiencing socioeconomic disadvantage and those experiencing socioeconomic advantage. This includes subgroups by income and gender.
3. To understand the process by which school feeding programs achieve (or fail to achieve) an impact on growth, cognitive development, and school performance.
4. To gather data that are useful for cost-benefit analysis.