Differences in age and developmental levels may result in changes in the ways males and females value themselves, and in the level of perceptual functioning from observers. Subjects (N=725) were divided into three groups. Self-raters (N=519) ranged from 6 to 18 years of age. Peer-raters (N=129) were their contemporaries (within one year). There were 77 adult-raters. Subjects were evenly divided by sex at each age level and within each group. All subjects completed a semantic-differential inventory, either a self-report or a same-item observer report. In all cases, self-reporting males had higher self-scores than females, the difference being more pronounced with older subjects. Peers and most of the adults saw self-reporters at a lower level than did the subjects themselves. Male adults showed lower ratings of female subjects than did female adults. Female adults showed lower perceptions of male subjects than they did of female subjects. Both male and female peers rated males higher than females. Males continue to rate themselves at a higher level than do females throughout the developmental stages. (Author/NRB)