Voicethread would be an amazing way for art students to share their critiques and break out of the conventional way of teaching the class.  Art teachers can scan student work to display for students to critique (amazingly the kids love seeing their work blown up when they can see all the nooks and crannies of their talents, but a voicethread could take it to the next level.    

Example of a voicethread for art history by Michelle Pacansky-Brock.  Her blog MPB Reflections-21st century teaching and learning is a great resource for instructional technology and art instruction.



Some other sites:

Art History Timelines

The art teacher’s guide to the internet blog (with many other great links): 


Art History in Just a Minute (short instructional videos!)