Subjects were 60 public school students divided into three groups of 20 each in kindergarten, third grade, and sixth grade. All children were within the normal range on verbal skills, as assessed by standard scores on the Peabody Picture Vocabulary Test, a measure highly correlated with verbal intelligence and expressive vocabulary skills. Transcripts of actual legal proceedings involving child witnesses were reviewed to establish a list of 35 legal terms. The legal terms selected were used frequently in direct examination of children and in courtroom proceedings in the presence of children. The legal terms were assigned randomly to two lists in consideration of the children's limited attention span. All children were tested individually. Grade-related patterns emerged in children's knowledge of legal terms and in their misunderstanding of terms. Results suggest that age-appropriate word choice in the examination of child witnesses may be an important factor in eliciting accurate testimony. Potential mediators of the relation between age and accurate knowledge of legal terminology (i.e., verbal skills, television viewing of court-related programs, direct experience with the legal system) also were explored. Implications for future research, court preparation, and training of legal professionals in age-appropriate examination of children are discussed. 4 tables and 22 references