Remember, whatever you download or copy an image it must have a Creative Commons license or you must be given permission to use it in another way.
You should always attribute the creator of the image and acknowledge the source of the image.
All Creative Common licences allow works to be used for educational purposes. A Createive common licence allows the creator to maintain copyright but allows the image to be used for non-commercial purposes.
Free Images can be obtained from the following sites.
Check out Larry Ferlazzo’s post on Free images
Sue Waters has written some good information on using images on the web and in blogs
