Abstract: Drawing from schema theory in cognitive psychology and the concept of schema instantiation in cognitive grammar, this paper introduces a schema-instantiation model for text development. This model posits that a text consists of two essential components: schema information and instance information. The paper argues that the schema-instance framework for text organization effectively maps cognitive routines related to schema instantiation onto the structural development of text. The progression of text is facilitated through this model, which functions through two primary mechanisms: the overarching influence of the schema over its instances and the elaboration of the schema by its instances. The findings demonstrate that this model provides substantial explanatory power for the progression of text across various genres, including narrative and expository texts.