A one-year project to explore the use of children's language served as a basis for staff development through the North Dakota Study Group on Evaluation. Children's conversations among themselves were observed and recorded within the classroom setting, and the content of the observations were used for planning curriculum and assessing children's progress. The documentation of this process was used as a basis for evaluating program effectiveness. The reality of piloting and developing this methodology has pointed to the difficulty of using this kind of data in relation to program evaluation. In developing the model, emphasis was placed on the child and his learning. The importance of relating to children as individuals and meeting children's individual needs was recognized. A K-1 class of 20 children was studied. Samples of children's spontaneous conversations and of workshop discussions of the samples are included. Samples of teacher's records that reveal friendship groups and children's choices of activities are also presented. The curriculum themes of rhythms and sounds, family, mathematical thinking, spatial relations, child's map of the world, and relationship process of curriculum are considered. (SW)