This study explored the association between children's vision and their school academic progress as reported by parents/guardians. Participants were 1,612 schoolchildren (722 6-7-year-olds, 890 12-13-year-olds) in randomly selected schools in Ireland. In advance of data collection, parents/guardians reported school performance as (a) much better than classmates (high-performance) (b) about the same as classmates (average-performance) (c) not as well as classmates (low-performance). Measurements included logMAR monocular visual acuities (with spectacles if worn, and pinhole) in the distance (3 m) and near (40 cm); the amplitude of accommodation; stereoacuity, colour vision assessment, and cyclopleged autorefraction. Controlling for confounders, children presenting with visual impairment (vision poorer than 0.3logMAR (6/12) in the 'better eye'), amblyopia ('lazy eye'), uncorrected refractive error (hyperopia [greater than or equal to]+3.50D and astigmatism [greater than or equal to]1.50DC), reduced for age ability to adjust focus from distance to near tasks (accommodation), impaired three-dimensional vision (stereoacuity), and defective colour vision were more likely to report low-performance in school. The majority of low-performing participants (68%) did not have an eye examination within the 12 months before data collection. Children with academic performance challenges ought to have a comprehensive eye examination, to detect potential vision problems for early intervention minimising any negative impact they may have on educational outcomes.