Water intake was described and quantified in samples of urban Guatemalan schoolchildren stratified by gender and socio-economic status. The frequency of consumption and quantity of plain water drinking was estimated from one- day pictorial registries of all beverages, foods and snacks consumed over a 24-h period collected from 449 3rd and 4th graders from two social classes: 230 from higher SES and 219 from lower SES. Plain water was reported by 28.1% of participants on the day of registry. Quantities consumed ranged from 250 to 2250 ml. For the 449 one-day intake records, a cumulative total of 62,000 mL of water consumption was reported. This constitutes an average of 138 ± 289 ml across all participants but, when divided by for water consumers only, the mean is 492 ± 352 ml. Given the relatively low percentage of children consuming water, more attention is needed to ensure freely available, safe, drinking water in the school environment.