Quantitative EEG aspects are studied with respect to age, sex and sociocultural parameters. A total of 162 children, from 7 to 11 years, neurologically and intellectually normal was studied. They were submitted to anamnesis, neurological examination, Raven test, school performance test, digital electroencephalogram and quantitative electroencephalogram analysis. There was a decrease in absolute and relative delta and theta power and an increase in alpha 2 relative power with the increase of age. These findings are similar to those observed in studies from Europe, Asia and North America. Absolute delta and alpha power were higher in children with better scores in school performance test. There were no significant differences in quantitative electroencephalographic parameters according to sex and the mother's educational level.