Introduction: it is important for students to have a good physical and mental health in order to acquire the knowledge properly. A study was conducted to determine the socio-educational factors associated with low visual acuity in primary school children from the National College of San Pedro-Piura. Material and methods: a cross-sectional analytical study involving 655 primary school students was conducted. The principal variable was low visual acuity, considered in those with values greater than 20/25, as assessed with the Snellen chart. P values, prevalence ratios and 95% confidence intervals were obtained using generalized linear models. Data were analyzed using STATA version 10.0. Results: a total of 599 students were evaluated, 17% (99) had low visual acuity. Sex was not related to the low visual acuity (p=0.832). As age increased, it was found that children who were between 8-10 and 11-15 years old had 46% (p=0.005) and 68% (p<0.001) less prevalence of low visual acuity, respectively, compared to the children who were 5-7 years old. Conclusions: it is concluded that one in six students had a visual disability associated with their age and grade level. This makes them more prone to problems in their grades, which may have implications for the rest of their lives. This should be taken into account by the institutions to monitor the proper education of children.