Bensound - makes a wide variety of music available under the Creative Commons licenses.

Creative Commons - is a tool that allows openly licensed and public domain images to be discovered and used by everyone.

Digital Public Library of America -  a portal that provides access to primary source digital collections across the US. Contains over 35,000,000 image, text, video, and sound files. 

Data Gif Maker by Google - uset data to create custom gifs/infographics.

Free Music Archive - offers free downloads under Creative Commons and other licenses.

Giphy - is a source for gifs.

Gratisography - is a vibrant community of creatives, sharing copyright free images.

Library of Congress - Public Domain or copyright cleared art and other materials.

NASA Image and Video Library - Public Domain photographs and video.

New Old Stock - Vintage photos from the public archives.  Free of known copyright restrictions.

Pexels - provides shared free stock videos for download.

Pixabay - is a vibrant community of creatives, sharing copyright free images and videos.

Pixnio - free images for anyone.

Purple Planet - provides royalty free music for download. 

Unsplash - over 1 million high resolution images free to use under the Unsplash license.

​Wikimedia Commons - freely usable media files to which anyone can contribute.

Slides Carnival - provides many templates for slide presentations.

Slides Go - provides many templates for slide presentations. 

Slides Mania - provides many templates for slide presentations. 

Sound Bible - has a royalty free sound effects section that allows free downloads under Creative Commons licenses.

Twisted Wave - online audio editing tool (similar to Audacity) can work on Chromebooks with no downloading required.

Videvo - provides free stock video and audio (music & effects).

World Digital Library - Images of historic items from countries around the world, curated by the U.S. Library of Congress and the United Nations.  Materials include photographs, maps, newspapers, journals, books, and manuscripts from museums, libraries, and national archives from around the world, representing over 100 languages.  Easily search by time period, institution, type of material, language, place, or topic.