This descriptive study compared language used by teachers and children in Ausubelian and Piagetian preschool programs during small group instruction and related learning activities. Instruction in the Ausubelian program (AP) was based on Ausubel's subsumption theory of learning while that in the Piagetian program (PP) was based on Piaget's theory of development. During one school year, 44 small group sessions were videotaped. Videotapes were coded for speaker, listener, category of utterances, reference to process or content, general or specific informational content, and correctly performed operations. Compared to teachers in the AP, teachers in the PP used questions more frequently than statements. Both groups of teachers more frequently used closed rather than open-ended questions. AP teachers and children referred more frequently than their counterparts in the PP to process rather than content. Children in the AP more frequently verbalized correctly performed mental operations than did children in the PP. Teachers in the PP employed consistent verbal strategies across tasks, whereas AP teachers varied their use of language by task. Comparison of results to findings of a concurrent study of children's improved understanding of logical concepts following instruction indicated that children in the AP performed significantly better than those in the PP. This appears to be an effect of the more frequent use of process language by teachers and children in the AP. (Author/RH)