The document describes two models of curriculum development: the Interaction Model and Taba's Model. The Interaction Model is a modification of Tyler's Model that views curriculum development as a dynamic process where the four elements (objectives, content, methods, evaluation) can be addressed in any order and influence each other. Taba's Model is a grassroots approach based on Tyler's Model that emphasizes teacher input and includes seven steps: diagnosis of needs, formulation of objectives, selection of content, organization of content, selection of learning experiences, organization of learning experiences, and evaluation. The document concludes by outlining a contemporary five-step framework for curriculum development that incorporates needs analysis, objectives, content selection and organization, implementation, and evaluation