This document discusses opening up educational resources through open educational resources (OER). It defines OER as openly accessible, freely available, shareable, discrete learning materials that can be reused and contextualized. Using OER allows educators to find existing high-quality resources rather than reinventing materials. While OER provide advantages like cost savings and encouraging best practices, they also have disadvantages like variable quality and need for contextualization. The document provides examples of OER types and templates for incorporating OER into course design. It also discusses trends in OER usage and issues to consider regarding OER and the "attention economy".