Children (< 18 years of age) face unique physiological and sociological obstacles in regards to hydration. Research regarding the impact of hydration on children’s cognitive performance lags considerably when compared to adults. Following methods of a systematic literature search, an exploratory review of current literature examining hydration and cognitive function in children is presented. Fourteen published studies in which fluid intake was manipulated or participants were grouped based on hydration status markers met a priori inclusion criteria. No studies altered hydration status via sweat loss. Many studies were conducted in participants’ school settings. Results were often reported as association between hydration status and performance with multiple covariates (e.g., IQ or socioeconomic status) versus contrast of raw scores between conditions, limiting direct, magnitude-based comparisons. Three major methodological themes were used to classify articles: (a) studies with a single, acute fluid intake intervention, (b) hydration interventions in which investigators attempted to intentionally alter fluid intake for an extended period, and (c) studies comparing cognitive results based on hydration status markers or reported fluid intake. The only intervention that consistently resulted in an improvement in cognitive task performance was acute fluid consumption. These results suggest encouragement to consume ~ 250 ml of water 20–60 min before challenging academic engagement may be advantageous to children. Research on mechanistic origins that explain acute fluid intake benefits on cognitive performance, differences in cognitive performance improvements due to fluid intake among children versus adults, and if routine academic tasks are improved by acute fluid intake is warranted.