Well, now they can.
Using Google Image Advanced Search allows students to set a variety of criteria when they search. Specifically, the "Usage Rights" option offers to limit results to those "labeled for reuse," generating entire banks of rights-friendly images for media projects.
The other options provide even greater control. Search by size, orientation (tall, landscape, etc)file type and color or black and white.
In fact--and I really LOVE this--click on the options link, and you can search for images with a dominant color. Here are the results for a "civil war" search with yellow selected. This is great for art teachers and projects that need some color-coordination.
You can even select the "Face" option, returning only portrait results.
Flickr creative commons is still a wonderful tool, obviously, though one that's frequently filtered in schools. Google Images now provides a viable and easy alternative.
