The malnutrition by excess of school age children is problem that may also be treated at school, because Children spend most of their time at school. It was studied knowledge about food of students from year four in primary school of private and semi-private schools of Talca city. An instrument was created and was applied to measure the knowledge of eating habits in children in sample of 273 students. The average percentage of knowledge that students have, was 61,4 ± 14;75%. Students from private schools had a better domain in the knowledge of eating habits (p<0.005). Insufficient knowledge can affect the nutritional status of children. This research must be confronted from a multifactorial perspective, even though, only knowledge does not indicate enough success in the nutritional recovery of the children.