Here are some fun websites that are art-related. I am updating often!
https://www.tate.org.uk/kids All sorts of great art stuff from the Tate Museum in London
https://www.albrightknox.org/community/ak-innovation-lab/artgames-20 The coolest artist-based games
http://cdn.99rooms.com/ an online exhibition that combines painting, photography and animation
https://www.nga.gov/education/kids.html You can create all sorts of things with the National Gallery of Art site
http://www.jacksonpollock.org/ Jackson Pollock action painting
http://bomomo.com/ Very cool abstract art creator
http://www.picassohead.com/create.html Make your own Picasso head!
http://www.zefrank.com/dtoy_vs_byokal/ create your own kaleidoscope
http://www.papercritters.com/pc.php Create paper origami style critters
http://www.happydaric.com/lite-brite/index.html Virtual Lite-Brite
http://www.getty.edu/gettygames/ Art Observation gameshttp://www.incredibleart.org/links/artgames.html Another comprehensive list of games and sites