Yaaruilta stories are told by children of all ages in Yupik-speaking Eskimo villages in Alaska. These stories are illustrated by figures sketched in mud with a ceremonial knife. The sustained involvement and effort of the children engaged in Yaaruilta may aid cognitive development by encouraging the learning of culturally related geometrical abstraction. With its demonstrative pronouns, the Yupik language may give children the tools to develop accurate geometrical figures. It is essential to document oral activities such as Yaaruilta before Eskimo languages are replaced by Western languages. In addition, parents and teachers outside Alaska can use this activity for language enrichment by providing mud and a plastic knife and by presenting children with a set of basic symbols. The child draws the symbols with the knife while simultaneously telling the story. In this way, Yaaruilta is similar to allowing a child to use a puppet while practicing language skills. Both methods reduce the child's inhibition. (Appendices include a set of symbols used in knife storytelling and two sample stories.) (CB)