The images found in the sites below can be used in any module, in any way, without citation. However, be sure to include a note in the notes section of your PPT OR in the Citations Google Sheet indicating where you found the image, so that we have a record of why we can use the image.
The images on these sites can be freely used in any way, in any module. However, you must provide attribution.
There are many other places that you can find images, but be sure to check for usage restrictions. While the sites listed below allow you to limit your results by license, be sure to double check each individual image to see the specific license and to note whether the creator has imposed any additional limitations (e.g., being attributed a certain way, or letting them know that you are using the image).
You can also search the web for "free stock photos" or "free clip art" to find many more sites. Again, be careful to check the Terms of Use for usage restrictions.