This study investigated the development of time concepts, comparing children of Afro-American and Anglo-American ethnic groups with each other and with results obtained by Piaget. A sample of 120 children aged seven, nine, and eleven years from one school were individually administered four time conservation tests (two on simultaneity and two on order of events). No significant relationships were found between seven, nine and eleven-year-old Afro-American and Anglo-American children in their performance on these four tests. With the exception of one group, all age levels were considered to be nonconservers by the Piaget 75 percent criterion, but conservation appeared to increase with age. (Author/MM)