OER CommonsOpen Educational Resources (OER) are teaching and learning materials that you may freely use and reuse at no cost, and without needing to ask permission. Unlike copyrighted resources, OER have been authored or created by an individual or organization that chooses to retain few, if any, ownership rights.From a single point of access in OER Commons, you can search, browse, and evaluate resources in OER Commons' growing collection of over 50,000 high-quality OER. Here are some curated collections to start exploring Full university courses,Interactive mini-lessons and simulations, Adaptations of existing open work, Open Textbooks, K-12 Lesson Plans, worksheets, and activities