The Smithsonian has released nearly 3 million images, 3D models, videos and more into the public domain! What this means is that anyone can search, find, download, use adapt and publish any of these artifacts without asking. So get searching and share this with your kids. Chances are if they are working on a research project, they may find media that can safely be used.
Smithsonian for the win!
Technology in the Classroom 