A survey was conducted to examine developmental changes in children's interpretations of their own television viewing, and the correlation between children's self reports and their mothers' estimates of the children's television viewing time. A total of 813 second, fifth, and eighth grade students were interviewed during one school year. These children also were asked to complete television logs for three one-week periods of late afternoon and evening television viewing, while their mothers supplied family data and estimates of the children's television viewing time. The children's diary estimates of their viewing showed strong correlation across the three time intervals. Correlations between general estimates of viewing time and diary estimates were generally positive, with the youngest children exhibiting the lowest consistency level. Although mother and child estimates were significantly correlated, the absolute differences between mother and child estimates were large. Overall, mothers estimated 10 to 16 more viewing hours per week than did the children. Partial correlation procedures failed to account for this difference. These analyses of estimates of children's television viewing time indicated few age differences in abilities to produce consistent self-report viewing data but wide discrepancies between mother and child viewing estimates. It was suggested that individuals' definitions of "viewing" could explain some of the discrepancies. (Author/RL)