There are so many Public Domain and open Creative Commons licensed media items available for your students to use. It's a good way to integrate some digital citizenship practice with students to talk about the ethics and legality of using other people's creative work and how to use properly use attribution. Here are a few links to get you and your students started. Depending on grade level and project allotted time, you may want to download a curated collection for them to choose from.

This is a curated and comprehensive list of links - resource for Open Resources.

Audio

• Bensound

• Purple Planet

• AshamaluevMusic

• Free Sound effects

• ZapSplat free sound effects

• Soundbible free sound effects

Video Clips

• Pond5 - 1,000 free video clips from historical footage and old movies

• NASA video gallery

• Videvo

• Pexels

• Videezy

• Mazawi video

• Covrr.co

• xStockVideo

Images

• Wikimedia Commons - https://commons.wikimedia.org

• Old book illustrations - http://www.oldbookillustrations.com/

• Public Domain archive - http://publicdomainarchive.com/

• SpaceX - https://www.flickr.com/photos/spacex/

• American Memory (Library of Congress) – http://memory.loc.gov/ammem/index.html

• America from the Great Depression to World War II – http://memory.loc.gov/ammem/fsowhome.html

• Civil War Photographs – http://memory.loc.gov/ammem/cwphtml/cwphome.html

• Daguerreotype Portraits and Views 1839-1864 – http://memory.loc.gov/ammem/daghtml/daghome.html

• Presidential Portraits – http://lcweb2.loc.gov/ammem/odmdhtml/preshome.html

• Art Images for College Teaching – http://arthist.cla.umn.edu/aict/index.html

• Archival Research Catalog (National Archives) – http://www.archives.gov/research/arc/index.html

• Art & Architecture (Art Serve) – http://rubens.anu.edu.au/

• Creative Commons – http://creativecommons.org/

• Department of Interior Photo Library – https://www.doi.gov/photos

• Discovery Education Clip Art – http://school.discoveryeducation.com/clipart/

• Digital Library System – http://images.fws.gov/

• Environmental Education System – http://web.centre.edu/enviro/Photos_files/Photos.htm

• Flickr – http://flickr.com

• Fotopedia – http://www.fotopedia.com/

• FreePhoto.com – http://www.freefoto.com/index.jsp

• FreeImages.com – http://www.freeimages.com/

• Free Stock Photos – http://www.freeimages.co.uk/

• USA.gov – http://www.usa.gov/

• Graphic Maps.com – http://www.graphicmaps.com/clipart.htm

• Great Images in NASA – http://grin.hq.nasa.gov/

• Iconfinder – https://www.iconfinder.com/

• Image After – http://www.imageafter.com/

• Images of American Political History – http://teachpol.tcnj.edu/amer_pol_hist/

• Map and Aerial Photography – http://libweb.uoregon.edu/map/

• Metropolitan Museum of Art – http://www.metmuseum.org/

• National Archives & Records Administration – http://www.archives.gov/

• Picturing the Century: 100 Years of Photography – http://www.archives.gov/exhibits/picturing_the_century/home.html

• New York Public Library Digital Gallery – http://www.nypl.org/digital/

• Pics for Learning – http://pics4learning.com/

• Public Domain Media – http://web4j1.lane.edu/libraryservices/mediainst/graphicsguide.html

• Social Science Data Lab – http://socsci.colorado.edu/GIF/

• U.S. Air Force Photos – http://www.af.mil/photos/

• U.S. Army Corps of Engineers Digital Library – http://cdm16021.contentdm.oclc.org/cdm/

• U.S. Department of Defense (multimedia) – http://www.defenselink.mil/multimedia/

• U.S. Federal Government Public Domain Images – http://stellar-one.com/public/us_federal_government_public_domain_images.htm

• Wikipedia Public Domain Image Sources – http://en.wikipedia.org/wiki/Wikipedia:Public_domain_image_resources

This list was largely borrowed from this EdTech Teacher resource.