1. NASA - http://www.nasa.gov/multimedia/imagegallery/

2. CIA - https://www.cia.gov/library/publications/the-world-factbook/

3. Library of Congress - http://memory.loc.gov/ammem/index.html

4. National Park Service - http://www.nps.gov/pub_aff/imagebase.html%20

5. Life Magazine 1860s – 1970s - http://images.google.com/hosted/life

6. List of resources – U.S. Government Image Portal - http://www.usa.gov/Topics/Graphics.shtml

7. Hubble Telescope Space Imagery - http://hubblesite.org/

8. Earth from space - http://visibleearth.nasa.gov/

9. Great NASA imagery - http://grin.hq.nasa.gov/

10. Health related imagery - http://phil.cdc.gov/phil/home.asp

11. Creative Commons imagery - https://images.google.com/?gws_rd=ssl , enter your search parameters > cogwheel on upper right > Advanced search > usage rights and choose appropriately.

12. Google image search (https://images.google.com/?gws_rd=ssl) > enter parameters > Search tools > Usage rights.

13. Wikimedia Commons - http://commons.wikimedia.org/wiki/Main_Page

14. The Commons on Flickr - https://www.flickr.com/commons

15. The John F. Kennedy Library - http://www.jfklibrary.org/

As Lesa Snider said in the source for this,

“As you can see, there are gobs of perfectly legal sources for images you can freely, so there’s really no excuse for stealing photos (because that’s what it really is). Besides being The Right Thing To Do, verifying your right to use an image protects you from some seriously nasty legal action and may even help you sleep better at night. Until next time, may the creative force be with you all!” – Lesa Snider

And…my personal “Thank you, Lesa!” to my teacher and friend.

Source:

http://www.macworld.com/article/2899637/the-ultimate-guide-to-finding-free-legal-images-online.html?utm_source=PhotoLesa+News&utm_campaign=e015dc035d-April_10_20154_9_2015&utm_medium=email&utm_term=0_4589f19617-e015dc035d-118838305