Art4kidshub is probably the most favorite place to find anything to draw. It is created by a really cool family and kid tested.
Abcya was a Computer class favorite when I taught Computer class at Grill Elementary. There are alot of fun art activities by grade level.
10 Best Art Museums approved by Parents Magazine is an article of different museums you can visit if you want to visit a museum online.
Funbrain is geared more for Grades 1-2. Lots of learning activities and some art activities.
PBSkids has alot to offer for ALL Elementary grade levels.
Metkids is one of my favorites if you want to see how art has been so interesting through out time. I love Art History and miss teaching it at Norton High School. You can see paintings, sculptures, and interesting facts about many artists. Enjoy discovering Art History.