Digital Exhibition and Collection Tours: Since we can't go to the actual museums right now, many are providing digital tours of shows and permanent collections. Some commercial art galleries and art spaces are doing the same thing or working to get things going. A good place to start is Artbasel.com.
Artist Videos: Some artists who already have online teach places in place are posting wonderful webinars and talks. Jordan Wolfson, based in Colorado is one. Last week, he posted a great discussion about Cezanne. Watch it on YouTube.