This document provides an overview of a lecture on curriculum theory. It discusses different conceptions of curriculum, including curriculum as the explicit, planned lessons and objectives, as well as the implicit and null curriculums which refer to the unintended learning of values and attitudes and ideas that are excluded. It also examines different approaches to curriculum, such as the academic idealist, techno-rationalist, learner-centered, and social reconstructionist perspectives. The lecture emphasizes that curriculum constitutes particular ways of reasoning and standards at the expense of others, and functions both to reproduce and transform society and culture.