Abstract
This is a descriptive comparative and quantitative study aimed to explore differences in family dynamics in primary school students form single parent and nuclear familiar structures in Yucatan Mexico. It was intended to determine differences in school performance due to either family structure or dynamics. A conventional sample of 80 students from nuclear families and 63 from a single parent families were included. It was found that that students form single parent families have a less positive view of the family, particularly regarding authority, communication and their perceived value of the family as a socials support network. School performance was related to family dynamics but not to family structure.