Try these open resources
Where can you find materials that you may use, re-use, re-mix, and/or share without violating copyright? A growing number of open source or open education resources (OERs) are available. Many of these sites, especially Creative Commons, offer ways for you to contribute your own works to the community.
Open Education Resources (OERs) & Other Sources for Educators
Creative Commons - Share, Remix, Reuse — Legally. Creative Commons licenses provide a flexible range of protections and freedoms for authors, artists, and educators.
HEAL Health Education Assets Library - HEAL "is a digital library that provides freely accessible digital teaching resources of the highest quality that meet the needs of today's health sciences educators and learners."
LibreTexts - "LibreTexts is a 501(c)(3) non-profit organization committed to freeing the textbook from the limitations and costs of traditional textbooks. Our open and freely accessible LibreTexts provide a more engaging learning experience for students without the financial burden."
MERLOT Multimedia Educational Resource for Learning and Online Teaching - Peer-reviewed online teaching and learning materials. From California State University System.
Creative Commons Image Search - Allows discovery of openly licensed and public domain images from museums, image banks, and other image repositories. Click on "filter" to search by image provider or license type. As of this writing (May 2019), only images are included but plans to add other media types as the database grows in size and use.
Google Advanced Image Search - Be sure to use the Usage Rights search field to limit by license type.
Library of Congress: American Memory - A free “digital record of American history and creativity.”
Library of Congress: Prints & Photographs Online Catalog - Photographs, prints, drawings, posters, and architectural drawings, and more.
NGA Images - Public domain artworks from the collections of the National Gallery of Art.
Noun Project - Free clip art images requiring creator credit.
NYPL Digital Gallery - Illuminated manuscripts, historical maps, vintage posters, rare prints, photographs, and more, from the New York Public Library.
Open ClipArt - Open Clipart is an online media collection of more than 160 000 vectorial graphics, entirely in the public domain. All graphics are stored using the Scalable Vector Graphics (SVG) format. Major standard supported all across the web, SVG files are very portable and can easily be scaled, edited, or printed without deformation. Join and contribute your own clipart to this public domain resource.
Pixabay - Pixabay offers millions of royalty-free stock photos and videos.
The Commons on Flickr - "The key goals of The Commons on Flickr are to firstly show you hidden treasures in the world's public photography archives, and secondly to show how your input and knowledge can help make these collections even richer." Includes images from the Library of Congress, the Smithsonian, the Getty Research Institute, and others.
Image credit: Collier, John, Jr, photographer. Penasco, New Mexico. A dance. New Mexico Penasco Penasco. Taos County United States, 1943. Jan. Photograph. https://www.loc.gov/item/2017842182/.
Film & Music sources
Are you looking for film clips or even complete feature films that are in the public domain? Here are some works that you can watch or even use in your own remixes.
Free Music Archive
A good resource for free or royalty-free music
Public Domain Movies
Who knew there were so many?
Uncle Earl's Classic Television Archive
Good collection of 20th century television programs.
What is "the public domain" anyway?
A work is considered to be in the public domain if it is not protected by copyright law. Typically, works in the public domain are free for the public to use in any way that they wish. A work may be in the public domain for a number of reasons, including:
Generally, copyright expires 95 years after the work's publication date although there are exceptions. January 1st of each year is Public Domain Day as works enter the public domain. Duke University hosts a Public Domain Day website celebrating the annual entrance of works into the public domain.
Copyright protection terms have changed over time so it can prove challenging to determine when a U.S. work falls into the public domain.